Proto-Indo-European (PIE) is the reconstructed common ancestor of the

Indo-European language family The Indo-European languages are a language family native to the overwhelming majority of Europe, the Iranian plateau, and the northern Indian subcontinent. Some European languages of this family, English, French, Portuguese, Russian, Dutch ...

. Its proposed features have been derived by

linguistic reconstruction Linguistic reconstruction is the practice of establishing the features of an unattested ancestor language of one or more given languages. There are two kinds of reconstruction: * Internal reconstruction uses irregularities in a single language to ...

from documented Indo-European languages. No direct record of Proto-Indo-European exists. Far more work has gone into reconstructing PIE than any other

proto-language In the tree model of historical linguistics, a proto-language is a postulated ancestral language from which a number of attested languages are believed to have descended by evolution, forming a language family. Proto-languages are usually unattest ...

, and it is the best understood of all proto-languages of its age. The majority of linguistic work during the 19th century was devoted to the reconstruction of PIE or its

daughter language In historical linguistics, a daughter language, also known as descendant language, is a language descended from another language, its mother language, through a process of genetic descent. If more than one language has developed from the same pro ...

s, and many of the modern techniques of linguistic reconstruction (such as the

comparative method In linguistics, the comparative method is a technique for studying the development of languages by performing a feature-by-feature comparison of two or more languages with common descent from a shared ancestor and then extrapolating backwards t ...

) were developed as a result. PIE is hypothesized to have been spoken as a single language from 4500 BC to 2500 BC during the Late

Neolithic The Neolithic period, or New Stone Age, is an Old World archaeological period and the final division of the Stone Age. It saw the Neolithic Revolution, a wide-ranging set of developments that appear to have arisen independently in several parts ...

to Early

Bronze Age The Bronze Age is a historic period, lasting approximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in some areas, and other early features of urban civilization. The Bronze Age is the second pri ...

, though estimates vary by more than a thousand years. According to the prevailing

Kurgan hypothesis The Kurgan hypothesis (also known as the Kurgan theory, Kurgan model, or steppe theory) is the most widely accepted proposal to identify the Proto-Indo-European homeland from which the Indo-European languages spread out throughout Europe and par ...

, the original homeland of the

Proto-Indo-Europeans The Proto-Indo-Europeans are a hypothetical prehistoric population of Eurasia who spoke Proto-Indo-European (PIE), the ancestor of the Indo-European languages according to linguistic reconstruction. Knowledge of them comes chiefly from t ...

may have been in the

Pontic–Caspian steppe The Pontic–Caspian steppe, formed by the Caspian steppe and the Pontic steppe, is the steppeland stretching from the northern shores of the Black Sea (the Pontus Euxinus of antiquity) to the northern area around the Caspian Sea. It extends ...

of eastern Europe. The linguistic reconstruction of PIE has provided insight into the pastoral

culture Culture () is an umbrella term which encompasses the social behavior, institutions, and norms found in human societies, as well as the knowledge, beliefs, arts, laws, customs, capabilities, and habits of the individuals in these groups.Tyl ...

and patriarchal

religion Religion is usually defined as a social- cultural system of designated behaviors and practices, morals, beliefs, worldviews, texts, sanctified places, prophecies, ethics, or organizations, that generally relates humanity to supernatural, ...

of its speakers. As speakers of Proto-Indo-European became isolated from each other through the

Indo-European migrations The Indo-European migrations were hypothesized migrations of Proto-Indo-European language (PIE) speakers, and subsequent migrations of people speaking derived Indo-European languages, which took place approx. 4000 to 1000 BCE, potentially expla ...

, the regional

dialect The term dialect (from Latin , , from the Ancient Greek word , 'discourse', from , 'through' and , 'I speak') can refer to either of two distinctly different types of Linguistics, linguistic phenomena: One usage refers to a variety (linguisti ...

s of Proto-Indo-European spoken by the various groups diverged, as each dialect underwent shifts in pronunciation (the

Indo-European sound laws As the Proto-Indo-European language (PIE) broke up, its sound system diverged as well, as evidenced in various sound laws associated with the daughter Indo-European languages. Especially notable is the palatalization that produced the satem lan ...

), morphology, and vocabulary. Over many centuries, these dialects transformed into the known ancient Indo-European

language Language is a structured system of communication. The structure of a language is its grammar and the free components are its vocabulary. Languages are the primary means by which humans communicate, and may be conveyed through a variety of met ...

s. From there, further linguistic divergence led to the evolution of their current descendants, the modern Indo-European languages. Today, the descendant languages of PIE with the most native speakers are

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many Latin American countries **Spanish cuisine Other places * Spanish, Ontario, Cana ...

English English usually refers to: * English language * English people English may also refer to: Peoples, culture, and language * ''English'', an adjective for something of, from, or related to England ** English national ide ...

Portuguese Portuguese may refer to: * anything of, from, or related to the country and nation of Portugal ** Portuguese cuisine, traditional foods ** Portuguese language, a Romance language *** Portuguese dialects, variants of the Portuguese language ** Portu ...

, Hindustani (

Hindi Hindi (Devanāgarī: or , ), or more precisely Modern Standard Hindi (Devanagari: ), is an Indo-Aryan language spoken chiefly in the Hindi Belt region encompassing parts of northern, central, eastern, and western India. Hindi has been de ...

and

Urdu Urdu (;"Urdu"
''

Bengali Bengali or Bengalee, or Bengalese may refer to: *something of, from, or related to Bengal, a large region in South Asia * Bengalis, an ethnic and linguistic group of the region * Bengali language, the language they speak ** Bengali alphabet, the w ...

Russian Russian(s) refers to anything related to Russia, including: *Russians (, ''russkiye''), an ethnic group of the East Slavic peoples, primarily living in Russia and neighboring countries *Rossiyane (), Russian language term for all citizens and peo ...

, Punjabi,

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

Persian Persian may refer to: * People and things from Iran, historically called ''Persia'' in the English language ** Persians, the majority ethnic group in Iran, not to be conflated with the Iranic peoples ** Persian language, an Iranian language of the ...

, French,

Marathi Marathi may refer to: *Marathi people, an Indo-Aryan ethnolinguistic group of Maharashtra, India *Marathi language, the Indo-Aryan language spoken by the Marathi people *Palaiosouda, also known as Marathi, a small island in Greece See also * * ...

Italian Italian(s) may refer to: * Anything of, from, or related to the people of Italy over the centuries ** Italians, an ethnic group or simply a citizen of the Italian Republic or Italian Kingdom ** Italian language, a Romance language *** Regional Ita ...

, and

Gujarati Gujarati may refer to: * something of, from, or related to Gujarat, a state of India * Gujarati people, the major ethnic group of Gujarat * Gujarati language, the Indo-Aryan language spoken by them * Gujarati languages, the Western Indo-Aryan sub- ...

. PIE is believed to have had an elaborate system of

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...

that included inflectional suffixes (analogous to English ''child, child's, children, children's'') as well as

ablaut In linguistics, the Indo-European ablaut (, from German ''Ablaut'' ) is a system of apophony (regular vowel variations) in the Proto-Indo-European language (PIE). An example of ablaut in English is the strong verb ''sing, sang, sung'' and its ...

(vowel alterations, as preserved in English ''sing, sang, sung, song'') and accent. PIE nominals and

pronouns In linguistics and grammar, a pronoun (list of glossing abbreviations, abbreviated ) is a word or a group of words that one may substitute for a noun or noun phrase. Pronouns have traditionally been regarded as one of the part of speech, parts o ...

had a complex system of

declension In linguistics, declension (verb: ''to decline'') is the changing of the form of a word, generally to express its syntactic function in the sentence, by way of some inflection. Declensions may apply to nouns, pronouns, adjectives, adverbs, and ar ...

, and

verbs A verb () is a word (part of speech) that in syntax generally conveys an action (''bring'', ''read'', ''walk'', ''run'', ''learn''), an occurrence (''happen'', ''become''), or a state of being (''be'', ''exist'', ''stand''). In the usual descrip ...

similarly had a complex system of

conjugation Conjugation or conjugate may refer to: Linguistics * Grammatical conjugation, the modification of a verb from its basic form * Emotive conjugation or Russell's conjugation, the use of loaded language Mathematics * Complex conjugation, the chang ...

. The PIE

phonology Phonology is the branch of linguistics that studies how languages or dialects systematically organize their sounds or, for sign languages, their constituent parts of signs. The term can also refer specifically to the sound or sign system of a ...

particles In the physical sciences, a particle (or corpuscule in older texts) is a small localized object which can be described by several physical or chemical properties, such as volume, density, or mass. They vary greatly in size or quantity, from su ...

numerals A numeral is a figure, symbol, or group of figures or symbols denoting a number. It may refer to: * Numeral system used in mathematics * Numeral (linguistics), a part of speech denoting numbers (e.g. ''one'' and ''first'' in English) * Numerical d ...

, and copula are also well-reconstructed. Asterisks are used as a conventional mark of reconstructed words, such as *, *, or *; these forms are the reconstructed ancestors of the modern English words ''water'', ''

hound A hound is a type of hunting dog used by hunters to track or chase prey. Description Hounds can be contrasted with gun dogs that assist hunters by identifying prey and/or recovering shot quarry. The hound breeds were the first hunting dogs. T ...

'', and ''three'', respectively.

Development of the hypothesis

No direct evidence of PIE exists; scholars have reconstructed PIE from its present-day descendants using the

. For example, compare the pairs of words in Italian and English: and ''foot'', and ''father'', and ''fish''. Since there is a consistent correspondence of the initial consonants that emerges far too frequently to be coincidental, one can infer that these languages stem from a common

parent language In the tree model of historical linguistics, a proto-language is a postulated ancestral language from which a number of attested languages are believed to have descended by evolution, forming a language family. Proto-languages are usually unattest ...

. Detailed analysis suggests a system of

sound laws A sound change, in historical linguistics, is a change in the pronunciation of a language. A sound change can involve the replacement of one speech sound (or, more generally, one phonetic feature value) by a different one (called phonetic chang ...

to describe the

phonetic Phonetics is a branch of linguistics that studies how humans produce and perceive sounds, or in the case of sign languages, the equivalent aspects of sign. Linguists who specialize in studying the physical properties of speech are phoneticians. ...

and

phonological Phonology is the branch of linguistics that studies how languages or dialects systematically organize their sounds or, for sign languages, their constituent parts of signs. The term can also refer specifically to the sound or sign system of a ...

changes from the hypothetical ancestral words to the modern ones. These laws have become so detailed and reliable as to support the

Neogrammarian The Neogrammarians (German: ''Junggrammatiker'', 'young grammarians') were a German school of linguists, originally at the University of Leipzig, in the late 19th century who proposed the Neogrammarian hypothesis of the regularity of sound change ...

rule: the Indo-European sound laws apply without exception. William Jones, an

Anglo-Welsh Welsh writing in English (Welsh language, Welsh: ''Llenyddiaeth Gymreig yn Saesneg''), (previously Anglo-Welsh literature) is a term used to describe works written in the English language by Welsh people, Welsh writers. The term ‘Anglo-Welsh ...

philologist Philology () is the study of language in oral and written historical sources; it is the intersection of textual criticism, literary criticism, history, and linguistics (with especially strong ties to etymology). Philology is also defined as th ...

and

puisne judge A puisne judge or puisne justice (; from french: puisné or ; , 'since, later' + , 'born', i.e. 'junior') is a dated term for an ordinary judge or a judge of lesser rank of a particular court. Use The term is used almost exclusively in common law ...

Bengal Bengal ( ; bn, বাংলা/বঙ্গ, translit=Bānglā/Bôngô, ) is a geopolitical, cultural and historical region in South Asia, specifically in the eastern part of the Indian subcontinent at the apex of the Bay of Bengal, predom ...

, caused an academic sensation when he postulated the common ancestry of

Sanskrit Sanskrit (; attributively , ; nominally , , ) is a classical language belonging to the Indo-Aryan branch of the Indo-European languages. It arose in South Asia after its predecessor languages had diffused there from the northwest in the late ...

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

, and

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

in 1786, but he was not the first to state such a hypothesis. In the 16th century, European visitors to the

Indian subcontinent The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian O ...

became aware of similarities between

Indo-Iranian language The Indo-Iranian languages (also Indo-Iranic languages or Aryan languages) constitute the largest and southeasternmost extant branch of the Indo-European language family (with over 400 languages), predominantly spoken in the geographical subre ...

s and European languages, and as early as 1653,

Marcus Zuerius van Boxhorn Marcus Zuerius van Boxhorn (August 28, 1612 – October 3, 1653) was a Dutch scholar (his Latinized name was Marcus Zuerius Boxhornius). Born in Bergen op Zoom, he was professor at the University of Leiden. He discovered the similarity among Indo- ...

had published a proposal for a

("Scythian") for the following language families: Germanic,

Romance Romance (from Vulgar Latin , "in the Roman language", i.e., "Latin") may refer to: Common meanings * Romance (love), emotional attraction towards another person and the courtship behaviors undertaken to express the feelings * Romance languages, ...

Baltic Baltic may refer to: Peoples and languages * Baltic languages, a subfamily of Indo-European languages, including Lithuanian, Latvian and extinct Old Prussian *Balts (or Baltic peoples), ethnic groups speaking the Baltic languages and/or originati ...

, Slavic,

Celtic Celtic, Celtics or Keltic may refer to: Language and ethnicity *pertaining to Celts, a collection of Indo-European peoples in Europe and Anatolia **Celts (modern) *Celtic languages **Proto-Celtic language * Celtic music *Celtic nations Sports Fo ...

, and

Iranian Iranian may refer to: * Iran, a sovereign state * Iranian peoples, the speakers of the Iranian languages. The term Iranic peoples is also used for this term to distinguish the pan ethnic term from Iranian, used for the people of Iran * Iranian lan ...

. In a memoir sent to the in 1767, , a French Jesuit who spent all his life in India, had specifically demonstrated the analogy between Sanskrit and European languages. According to current academic consensus, Jones's famous work of 1786 was less accurate than his predecessors', as he erroneously included

Egyptian Egyptian describes something of, from, or related to Egypt. Egyptian or Egyptians may refer to: Nations and ethnic groups * Egyptians, a national group in North Africa ** Egyptian culture, a complex and stable culture with thousands of years of ...

Japanese Japanese may refer to: * Something from or related to Japan, an island country in East Asia * Japanese language, spoken mainly in Japan * Japanese people, the ethnic group that identifies with Japan through ancestry or culture ** Japanese diaspor ...

and

Chinese Chinese can refer to: * Something related to China * Chinese people, people of Chinese nationality, citizenship, and/or ethnicity **''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation ** List of ethnic groups in China, people of va ...

in the Indo-European languages, while omitting

. In 1818,

Rasmus Christian Rask Rasmus Kristian Rask (; born Rasmus Christian Nielsen Rasch; 22 November 1787 – 14 November 1832) was a Danish linguist and philologist. He wrote several grammars and worked on comparative phonology and morphology. Rask traveled extensively to ...

elaborated the set of correspondences in his prize essay ('Investigation of the Origin of the Old Norse or Icelandic Language'), where he argued that

Old Norse Old Norse, Old Nordic, or Old Scandinavian, is a stage of development of North Germanic languages, North Germanic dialects before their final divergence into separate Nordic languages. Old Norse was spoken by inhabitants of Scandinavia and t ...

was related to the Germanic languages, and had even suggested a relation to the Baltic, Slavic, Greek, Latin and Romance languages. In 1816,

Franz Bopp Franz Bopp (; 14 September 1791 – 23 October 1867) was a German linguist known for extensive and pioneering comparative work on Indo-European languages. Early life Bopp was born in Mainz, but the political disarray in the Republic of Mai ...

published ''On the System of Conjugation in Sanskrit'', in which he investigated a common origin of Sanskrit, Persian, Greek, Latin, and German. In 1833, he began publishing the ''Comparative Grammar of Sanskrit,

Zend Zend or Zand ( pal, 𐭦𐭭𐭣) is a Zoroastrian technical term for exegetical glosses, paraphrases, commentaries and translations of the Avesta's texts. The term ''zand'' is a contraction of the Avestan language word ' (, meaning "interpretat ...

, Greek, Latin, Lithuanian, Old Slavic, Gothic, and German''. In 1822,

Jacob Grimm Jacob Ludwig Karl Grimm (4 January 1785 – 20 September 1863), also known as Ludwig Karl, was a German author, linguist, philologist, jurist, and folklorist. He is known as the discoverer of Grimm's law of linguistics, the co-author of th ...

formulated what became known as

Grimm's law Grimm's law (also known as the First Germanic Sound Shift) is a set of sound laws describing the Proto-Indo-European (PIE) stop consonants as they developed in Proto-Germanic in the 1st millennium BC. First systematically put forward by Jacob Grim ...

as a general rule in his . Grimm showed correlations between the Germanic and other Indo-European languages and demonstrated that sound change systematically transforms all words of a language. From the 1870s, the Neogrammarians proposed that sound laws have no exceptions, as illustrated by

Verner's law Verner's law describes a historical sound change in the Proto-Germanic language whereby consonants that would usually have been the voiceless fricatives , , , , , following an unstressed syllable, became the voiced fricatives , , , , . The law was ...

, published in 1876, which resolved apparent exceptions to Grimm's law by exploring the role of accent (stress) in language change.

August Schleicher August Schleicher (; 19 February 1821 – 6 December 1868) was a German linguist. His great work was ''A Compendium of the Comparative Grammar of the Indo-European Languages'' in which he attempted to reconstruct the Proto-Indo-European languag ...

's ''A Compendium of the Comparative Grammar of the Indo-European, Sanskrit, Greek and Latin Languages'' (1874–77) represented an early attempt to reconstruct the proto-Indo-European language. By the early 1900s,

Indo-Europeanist Indo-European studies is a field of linguistics and an interdisciplinary field of study dealing with Indo-European languages, both current and extinct. The goal of those engaged in these studies is to amass information about the hypothetical pro ...

s had developed well-defined descriptions of PIE which scholars still accept today. Later, the discovery of the

Anatolian Anatolian or anatolica may refer to: * Anything of, from, or related to the region Anatolia * Anatolians, ancient Indo-European peoples who spoke the Anatolian languages * Anatolian High School, a type of Turkish educational institution * Anatol ...

and

Tocharian languages The Tocharian (sometimes ''Tokharian'') languages ( or ), also known as ''Arśi-Kuči'', Agnean-Kuchean or Kuchean-Agnean, are an extinct branch of the Indo-European language family spoken by inhabitants of the Tarim Basin, the Tocharians. The l ...

added to the corpus of descendant languages. A subtle new principle won wide acceptance: the

laryngeal theory The laryngeal theory is a theory in the historical linguistics of the Indo-European languages positing that: * The Proto-Indo-European language (PIE) had a series of phonemes beyond those reconstructable by the comparative method. That is, the ...

, which explained irregularities in the reconstruction of Proto-Indo-European phonology as the effects of hypothetical sounds which no longer exist in all languages documented prior to the excavation of

cuneiform Cuneiform is a logo-syllabic script that was used to write several languages of the Ancient Middle East. The script was in active use from the early Bronze Age until the beginning of the Common Era. It is named for the characteristic wedge-sha ...

tablets in Anatolian.

Julius Pokorny Julius Pokorny (12 June 1887 – 8 April 1970) was an Austrian-Czech linguist and scholar of the Celtic languages, particularly Irish, and a supporter of Irish nationalism. He held academic posts in Austrian and German universities. Early life a ...

's ('Indo-European Etymological Dictionary', 1959) gave a detailed, though conservative, overview of the lexical knowledge accumulated by 1959.

Jerzy Kuryłowicz Jerzy Kuryłowicz (; 26 August 1895 – 28 January 1978) was a Polish linguist who studied Indo-European languages. Life Born in Stanislawow, Austria-Hungary. He was a Polish historical linguist, structuralist and language theoretician, deeply i ...

's 1956 ''Apophonie'' gave a better understanding of

Indo-European ablaut In linguistics, the Indo-European ablaut (, from German ''Ablaut'' ) is a system of apophony (regular vowel variations) in the Proto-Indo-European language (PIE). An example of ablaut in English is the strong verb ''sing, sang, sung'' and its ...

. From the 1960s, knowledge of Anatolian became robust enough to establish its relationship to PIE.

Historical and geographical setting

Scholars have proposed multiple hypotheses about when, where, and by whom PIE was spoken. The

, first put forward in 1956 by

Marija Gimbutas Marija Gimbutas ( lt, Marija Gimbutienė, ; January 23, 1921 – February 2, 1994) was a Lithuanian archaeologist and anthropologist known for her research into the Neolithic and Bronze Age cultures of " Old Europe" and for her Kurgan hypothesis, ...

, has become the most popular. It proposes that the original speakers of PIE were the

Yamnaya culture The Yamnaya culture or the Yamna culture (russian: Ямная культура, ua, Ямна культура literal translation, lit. 'culture of pits'), also known as the Pit Grave culture or Ochre Grave culture, was a late Copper Age to ea ...

associated with the

kurgan A kurgan is a type of tumulus constructed over a grave, often characterized by containing a single human body along with grave vessels, weapons and horses. Originally in use on the Pontic–Caspian steppe, kurgans spread into much of Central Asi ...

s (burial mounds) on the

north of the Black Sea. According to the theory, they were

nomadic pastoralists Nomadic pastoralism is a form of pastoralism in which livestock are herded in order to seek for fresh pastures on which to graze. True nomads follow an irregular pattern of movement, in contrast with transhumance, where seasonal pastures are fix ...

who domesticated the horse, which allowed them to migrate across Europe and Asia in wagons and chariots. By the early 3rd millennium BC, they had expanded throughout the Pontic–Caspian steppe and into eastern Europe. Other theories include the

Anatolian hypothesis The Anatolian hypothesis, also known as the Anatolian theory or the sedentary farmer theory, first developed by British people, British Archaeology, archaeologist Colin Renfrew in 1987, proposes that the dispersal of Proto-Indo-Europeans origina ...

, which posits that PIE spread out from Anatolia with agriculture beginning 7500–6000 BC, the

Armenian hypothesis The Armenian hypothesis, also known as the Near Eastern model, is a theory of the Proto-Indo-European homeland, initially proposed by linguists Tamaz V. Gamkrelidze and Vyacheslav Ivanov in the early 1980s, which suggests that the Proto-Indo-Eu ...

, the

Paleolithic continuity paradigm The Proto-Indo-European homeland (or Indo-European homeland) was the prehistoric linguistic homeland of the Proto-Indo-European language (PIE). From this region, its speakers Indo-European migrations, migrated east and west, and went on to form ...

, and the

indigenous Aryans Indigenous Aryanism, also known as the Indigenous Aryans theory (IAT) and the Out of India theory (OIT), is the conviction that the Aryans are indigenous to the Indian subcontinent, and that the Indo-European languages radiated out from a homela ...

theory. Out of all the theories for a PIE homeland, the Kurgan and Anatolian hypotheses are the ones most widely accepted, and also the ones most debated against each other. The question of a PIE homeland is considered to be the biggest controversy in PIE studies, which some linguists think may never be solved. IndoEuropeanTree

Descendants

The table lists the main Indo-European language families, comprising the languages descended from Proto-Indo-European. Commonly proposed subgroups of Indo-European languages include

Italo-Celtic In historical linguistics, Italo-Celtic is a hypothetical grouping of the Italic and Celtic branches of the Indo-European language family on the basis of features shared by these two branches and no others. There is controversy about the causes o ...

Graeco-Aryan Graeco-Aryan, or Graeco-Armeno-Aryan, is a hypothetical clade within the Indo-European family that would be the ancestor of Greek, Armenian, and the Indo-Iranian languages. The Graeco-Armeno-Aryan group supposedly branched off from the parent I ...

Graeco-Armenian Graeco-Armenian (or Helleno-Armenian) is the hypothetical common ancestor of Greek and Armenian that postdates Proto-Indo-European. Its status is somewhat similar to that of the Italo-Celtic grouping: each is widely considered plausible without b ...

Graeco-Phrygian Graeco-Phrygian () is a proposed subgroup of the Indo-European language family which comprises the Hellenic and Phrygian languages. Modern consensus views Greek as the closest relative of Phrygian, a position that is supported by Brixhe, N ...

Daco-Thracian The linguistic classification of the ancient Thracian language has long been a matter of contention and uncertainty, and there are widely varying hypotheses regarding its position among other Paleo-Balkan languages. It is not contested, however, th ...

, and

Thraco-Illyrian The term Thraco-Illyrian refers to a hypothesis according to which the Daco-Thracian and Illyrian languages comprise a distinct branch of Indo-European. Thraco-Illyrian is also used as a term merely implying a Thracian- Illyrian interference, mix ...

. There are numerous lexical similarities between the Proto-Indo-European and

Proto-Kartvelian The Proto-Kartvelian language, or Common Kartvelian ( ka, წინარექართველური ენა, tr), is the linguistic reconstruction of the common ancestor of the Kartvelian languages, which was spoken by the ancestors of th ...

languages due to early

language contact Language contact occurs when speakers of two or more languages or varieties interact and influence each other. The study of language contact is called contact linguistics. When speakers of different languages interact closely, it is typical for th ...

, though some morphological similarities—notably the

, which is remarkably similar to the root ablaut system reconstructible for Proto-Kartvelian.

Marginally attested languages

The

Lusitanian language Lusitanian (so named after the Lusitani or Lusitanians) was an Indo-European Paleohispanic language. There has been support for either a connection with the ancient Italic languages or Celtic languages. It is known from only six sizeable inscri ...

was a marginally attested language spoken in areas near the border between present-day

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

and

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

. The

Venetic Venetic is an extinct Indo-European language, usually classified into the Italic subgroup, that was spoken by the Veneti people in ancient times in northeast Italy (Veneto and Friuli) and part of modern Slovenia, between the Po Delta and ...

and

Liburnian The Liburnians or Liburni ( grc, Λιβυρνοὶ) were an ancient tribe inhabiting the district called Liburnia, a coastal region of the northeastern Adriatic between the rivers ''Arsia'' ( Raša) and ''Titius'' ( Krka) in what is now Croatia ...

languages known from the North Adriatic region are sometimes classified as Italic. Albanian and Greek are the only surviving Indo-European descendants of a Paleo-Balkan language area, named for their occurrence in or in the vicinity of the

Balkan peninsula The Balkans ( ), also known as the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throughout the who ...

. Most of the other languages of this area—including Illyrian,

Thracian The Thracians (; grc, Θρᾷκες ''Thrāikes''; la, Thraci) were an Indo-European speaking people who inhabited large parts of Eastern and Southeastern Europe in ancient history.. "The Thracians were an Indo-European people who occupied t ...

, and Dacian—do not appear to be members of any other subfamilies of PIE, but are so poorly attested that proper classification of them is not possible. Forming an exception, Phrygian is sufficiently well-attested to allow proposals of a particularly close affiliation with Greek, and a

branch of Indo-European is becoming increasingly accepted.

Phonology

Proto-Indo-European

has been reconstructed in some detail. Notable features of the most widely accepted (but not uncontroversial) reconstruction include: *three series of

stop consonant In phonetics, a plosive, also known as an occlusive or simply a stop, is a pulmonic consonant in which the vocal tract is blocked so that all airflow ceases. The occlusion may be made with the tongue tip or blade (, ), tongue body (, ), lips ...

s reconstructed as

voiceless In linguistics, voicelessness is the property of sounds being pronounced without the larynx vibrating. Phonologically, it is a type of phonation, which contrasts with other states of the larynx, but some object that the word phonation implies v ...

voiced Voice or voicing is a term used in phonetics and phonology to characterize speech sounds (usually consonants). Speech sounds can be described as either voiceless (otherwise known as ''unvoiced'') or voiced. The term, however, is used to refer ...

, and

breathy voice Breathy voice (also called murmured voice, whispery voice, soughing and susurration) is a phonation in which the vocal folds vibrate, as they do in normal (modal) voicing, but are adjusted to let more air escape which produces a sighing-like ...

d; *

sonorant In phonetics and phonology, a sonorant or resonant is a speech sound that is produced with continuous, non-turbulent airflow in the vocal tract; these are the manners of articulation that are most often voiced in the world's languages. Vowels are ...

consonants that could be used syllabically; *three so-called laryngeal consonants, whose exact pronunciation is not well-established but which are believed to have existed in part based on their detectable effects on adjacent sounds; *the

fricative A fricative is a consonant produced by forcing air through a narrow channel made by placing two articulators close together. These may be the lower lip against the upper teeth, in the case of ; the back of the tongue against the soft palate in t ...

vowel A vowel is a syllabic speech sound pronounced without any stricture in the vocal tract. Vowels are one of the two principal classes of speech sounds, the other being the consonant. Vowels vary in quality, in loudness and also in quantity (leng ...

system in which and were the most frequently occurring vowels.

Notation

Vowels

The vowels in commonly used notation are:

Consonants

The corresponding consonants in commonly used notation are:

Accent

The

Proto-Indo-European accent Proto-Indo-European accent refers to the accentual (stress) system of the Proto-Indo-European language. Description Proto-Indo-European (PIE) is usually reconstructed as having had variable lexical stress: the placement of the stress in a word ...

is reconstructed today as having had variable lexical stress, which could appear on any syllable and whose position often varied among different members of a paradigm (e.g. between singular and plural of a verbal paradigm). Stressed syllables received a higher pitch; therefore it is often said that PIE had a

pitch accent A pitch-accent language, when spoken, has word accents in which one syllable in a word or morpheme is more prominent than the others, but the accentuated syllable is indicated by a contrasting pitch ( linguistic tone) rather than by loudness ( ...

. The location of the stress is associated with ablaut variations, especially between normal-grade vowels ( and ) and zero-grade (i.e. lack of a vowel), but not entirely predictable from it. The accent is best preserved in

Vedic Sanskrit Vedic Sanskrit was an ancient language of the Indo-Aryan subgroup of the Indo-European language family. It is attested in the Vedas and related literature compiled over the period of the mid- 2nd to mid-1st millennium BCE. It was orally preser ...

and (in the case of nouns)

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

, and indirectly attested in a number of phenomena in other IE languages. To account for mismatches between the accent of Vedic Sanskrit and Ancient Greek, as well as a few other phenomena, a few historical linguists prefer to reconstruct PIE as a

tone language Tone is the use of pitch in language to distinguish lexical or grammatical meaning – that is, to distinguish or to inflect words. All verbal languages use pitch to express emotional and other paralinguistic information and to convey empha ...

where each

morpheme A morpheme is the smallest meaningful Constituent (linguistics), constituent of a linguistic expression. The field of linguistics, linguistic study dedicated to morphemes is called morphology (linguistics), morphology. In English, morphemes are ...

had an inherent tone; the sequence of tones in a word then evolved, according to that hypothesis, into the placement of lexical stress in different ways in different IE branches.

Morphology

Root

Proto-Indo-European root The root (linguistics), roots of the reconstructed Proto-Indo-European language (PIE) are basic parts of words that carry a lexical (semiotics), lexical meaning, so-called morphemes. PIE roots usually have verbal meaning like "to eat" or "to run ...

s were

affix In linguistics, an affix is a morpheme that is attached to a word stem to form a new word or word form. Affixes may be derivational, like English ''-ness'' and ''pre-'', or inflectional, like English plural ''-s'' and past tense ''-ed''. They ar ...

-lacking

s which carried the core

lexical Lexical may refer to: Linguistics * Lexical corpus or lexis, a complete set of all words in a language * Lexical item, a basic unit of lexicographical classification * Lexicon, the vocabulary of a person, language, or branch of knowledge * Lexical ...

meaning of a word and were used to derive related words (cf. the English root "-''friend''-", from which are derived related words such as ''friendship,'' ''friendly'', ''befriend'', and newly coined words such as ''unfriend''). Proto-Indo-European was probably a

fusional language Fusional languages or inflected languages are a type of synthetic language, distinguished from agglutinative languages by their tendency to use a single inflectional morpheme to denote multiple grammatical, syntactic, or semantic features. Fo ...

, in which

inflection In linguistic morphology, inflection (or inflexion) is a process of word formation in which a word is modified to express different grammatical categories such as tense, case, voice, aspect, person, number, gender, mood, animacy, and defin ...

al morphemes signalled the grammatical relationships between words. This dependence on inflectional morphemes means that roots in PIE, unlike those in English, were rarely used without affixes. A root plus a

suffix In linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns, adjectives, and verb endings, which form the conjugation of verbs. Suffixes can carry ...

formed a

word stem In linguistics, a word stem is a part of a word responsible for its lexical meaning. The term is used with slightly different meanings depending on the morphology of the language in question. In Athabaskan linguistics, for example, a verb stem is ...

, and a word stem plus a desinence (usually an ending) formed a word.

Ablaut

Many morphemes in Proto-Indo-European had short ''e'' as their inherent vowel; the

is the change of this short ''e'' to short ''o'', long ''e'' (ē), long ''o'' (''ō''), or no vowel. This variation in vowels occurred both within

inflectional morphology In linguistic morphology, inflection (or inflexion) is a process of word formation in which a word is modified to express different grammatical categories such as tense, case, voice, aspect, person, number, gender, mood, animacy, and defin ...

(e.g., different grammatical forms of a noun or verb may have different vowels) and

derivational morphology Morphological derivation, in linguistics, is the process of forming a new word from an existing word, often by adding a prefix or suffix, such as For example, ''unhappy'' and ''happiness'' derive from the root word ''happy.'' It is differentiat ...

(e.g., a verb and an associated abstract

verbal noun A verbal noun or gerundial noun is a verb form that functions as a noun. An example of a verbal noun in English grammar, English is 'sacking' as in the sentence "The sacking of the city was an epochal event" (''sacking'' is a noun formed from the ...

may have different vowels). Categories that PIE distinguished through ablaut were often also identifiable by contrasting endings, but the loss of these endings in some later Indo-European languages has led them to use ablaut alone to identify grammatical categories, as in the Modern English words ''sing'', ''sang'', ''sung''.

Noun

Proto-Indo-European nouns Proto-Indo-European nominals include nouns, adjectives, and pronouns. Their grammatical forms and meanings have been reconstructed by modern linguists, based on similarities found across all Indo-European languages. This article discusses nouns a ...

were probably declined for eight or nine cases: *

nominative In grammar, the nominative case (abbreviated ), subjective case, straight case or upright case is one of the grammatical cases of a noun or other part of speech, which generally marks the subject of a verb or (in Latin and formal variants of Engl ...

: marks the subject of a verb, such as ''They'' in ''They ate''. Words that follow a linking verb (

copulative verb In linguistics, a copula (plural: copulas or copulae; abbreviated ) is a word or phrase that links the subject of a sentence to a subject complement, such as the word ''is'' in the sentence "The sky is blue" or the phrase ''was not being'' ...

) and restate the subject of that verb also use the nominative case. Thus, both ''They'' and ''linguists'' are in the nominative case in ''They are linguists''. The nominative is the dictionary form of the noun. *

accusative The accusative case (abbreviated ) of a noun is the grammatical case used to mark the direct object of a transitive verb. In the English language, the only words that occur in the accusative case are pronouns: 'me,' 'him,' 'her,' 'us,' and ‘the ...

: used for the

direct object In linguistics, an object is any of several types of arguments. In subject-prominent, nominative-accusative languages such as English, a transitive verb typically distinguishes between its subject and any of its objects, which can include but ...

of a

transitive verb A transitive verb is a verb that accepts one or more objects, for example, 'cleaned' in ''Donald cleaned the window''. This contrasts with intransitive verbs, which do not have objects, for example, 'panicked' in ''Donald panicked''. Transitiv ...

. *

genitive In grammar, the genitive case (abbreviated ) is the grammatical case that marks a word, usually a noun, as modifying another word, also usually a noun—thus indicating an attributive relationship of one noun to the other noun. A genitive can al ...

: marks a

noun A noun () is a word that generally functions as the name of a specific object or set of objects, such as living creatures, places, actions, qualities, states of existence, or ideas.Example nouns for: * Living creatures (including people, alive, d ...

as modifying another noun. *

dative In grammar, the dative case (abbreviated , or sometimes when it is a core argument) is a grammatical case used in some languages to indicate the recipient or beneficiary of an action, as in "Maria Jacobo potum dedit", Latin for "Maria gave Jacob a ...

: used to indicate the indirect object of a transitive verb, such as ''Jacob'' in ''Maria gave Jacob a drink''. *

instrumental An instrumental is a recording normally without any vocals, although it might include some inarticulate vocals, such as shouted backup vocals in a big band setting. Through semantic widening, a broader sense of the word song may refer to instru ...

: marks the ''instrument'' or means by, or with, which the subject achieves or accomplishes an action. It may be either a physical object or an abstract concept. *

ablative In grammar, the ablative case (pronounced ; sometimes abbreviated ) is a grammatical case for nouns, pronouns, and adjectives in the grammars of various languages; it is sometimes used to express motion away from something, among other uses. T ...

: used to express motion away from something. *

locative In grammar, the locative case (abbreviated ) is a grammatical case which indicates a location. It corresponds vaguely to the English prepositions "in", "on", "at", and "by". The locative case belongs to the general local cases, together with the ...

: corresponds vaguely to the English prepositions ''in'', ''on'', ''at'', and ''by''. *

vocative In grammar, the vocative Grammatical case, case (list of glossing abbreviations, abbreviated ) is a grammatical case which is used for a noun that identifies a person (animal, object, etc.) being addressed, or occasionally for the noun modifiers ...

: used for a word that identifies an addressee. A vocative expression is one of direct address where the identity of the party spoken to is set forth expressly within a sentence. For example, in the sentence, "I don't know, John", ''John'' is a vocative expression that indicates the party being addressed. *

allative In grammar, the allative case (; abbreviated ; from Latin ''allāt-'', ''afferre'' "to bring to") is a type of locative grammatical case. The term allative is generally used for the lative case in the majority of languages that do not make finer ...

: used as a type of

locative case In grammar, the locative case (abbreviated ) is a grammatical case which indicates a location. It corresponds vaguely to the English prepositions "in", "on", "at", and "by". The locative case belongs to the general local cases, together with the ...

that expresses movement towards something. It was preserved in Anatolian (particularly Old Hittite), and fossilized traces of it have been found in Greek. Its PIE shape is uncertain, with candidates including ''*-h₂(e)'', ''*-(e)h₂'', or ''*-a''. Late Proto-Indo-European had three

grammatical gender In linguistics, grammatical gender system is a specific form of noun class system, where nouns are assigned with gender categories that are often not related to their real-world qualities. In languages with grammatical gender, most or all nouns ...

s: * masculine * feminine * neuter This system is probably derived from an older two-gender system, attested in Anatolian languages:

common Common may refer to: Places * Common, a townland in County Tyrone, Northern Ireland * Boston Common, a central public park in Boston, Massachusetts * Cambridge Common, common land area in Cambridge, Massachusetts * Clapham Common, originally com ...

(or

animate Animation is a method by which still figures are manipulated to appear as moving images. In traditional animation, images are drawn or painted by hand on transparent celluloid sheets to be photographed and exhibited on film. Today, most anima ...

) and neuter (or inanimate) gender. The feminine gender only arose in the later period of the language. Neuter nouns collapsed the nominative, vocative and accusative into a single form, the plural of which used a special

collective A collective is a group of entities that share or are motivated by at least one common issue or interest, or work together to achieve a common objective. Collectives can differ from cooperatives in that they are not necessarily focused upon an ...

suffix (manifested in most descendants as ''-a''). This same collective suffix in extended forms and (respectively on thematic and athematic nouns, becoming ''-ā'' and ''-ī'' in the early daughter languages) became used to form feminine nouns from masculines. All nominals distinguished three

numbers A number is a mathematical object used to count, measure, and label. The original examples are the natural numbers 1, 2, 3, 4, and so forth. Numbers can be represented in language with number words. More universally, individual numbers can ...

: * singular * dual * plural These numerals were also distinguished in verbs (see

below Below may refer to: *Earth *Ground (disambiguation) *Soil *Floor *Bottom (disambiguation) Bottom may refer to: Anatomy and sex * Bottom (BDSM), the partner in a BDSM who takes the passive, receiving, or obedient role, to that of the top or ...

), requiring

agreement Agreement may refer to: Agreements between people and organizations * Gentlemen's agreement, not enforceable by law * Trade agreement, between countries * Consensus, a decision-making process * Contract, enforceable in a court of law ** Meeting o ...

with their subject nominal.

Pronoun

Proto-Indo-European pronouns Proto-Indo-European pronouns have been reconstructed by modern linguists, based on similarities found across all Indo-European languages. This article lists and discusses the hypothesised forms. Proto-Indo-European (PIE) pronouns, especially demo ...

are difficult to reconstruct, owing to their variety in later languages. PIE had personal

pronoun In linguistics and grammar, a pronoun (abbreviated ) is a word or a group of words that one may substitute for a noun or noun phrase. Pronouns have traditionally been regarded as one of the parts of speech, but some modern theorists would not co ...

s in the first and second

grammatical person In linguistics, grammatical person is the grammatical distinction between deictic references to participant(s) in an event; typically the distinction is between the speaker ( first person), the addressee ( second person), and others (third pers ...

, but not the third person, where

demonstrative pronoun Demonstratives (abbreviated ) are words, such as ''this'' and ''that'', used to indicate which entities are being referred to and to distinguish those entities from others. They are typically deictic; their meaning depending on a particular frame ...

s were used instead. The personal pronouns had their own unique forms and endings, and some had two distinct stems; this is most obvious in the first person singular where the two stems are still preserved in English ''I'' and ''me''. There were also two varieties for the accusative, genitive and dative cases, a stressed and an

enclitic In morphology and syntax, a clitic (, backformed from Greek "leaning" or "enclitic"Crystal, David. ''A First Dictionary of Linguistics and Phonetics''. Boulder, CO: Westview, 1980. Print.) is a morpheme that has syntactic characteristics of a wo ...

form.

Verb

Proto-Indo-European verbs Proto-Indo-European verbs reflect a complex system of morphology, more complicated than the substantive, with verbs categorized according to their aspect, using multiple grammatical moods and voices, and being conjugated according to person, nu ...

, like the nouns, exhibited a system of ablaut. The most basic categorisation for the reconstructed Indo-European verb is

grammatical aspect In linguistics, aspect is a grammatical category that expresses how an action, event, or state, as denoted by a verb, extends over time. Perfective aspect is used in referring to an event conceived as bounded and unitary, without reference to ...

. Verbs are classed as: *

stative According to some linguistics theories, a stative verb is a verb that describes a state of being, in contrast to a dynamic verb, which describes an action. The difference can be categorized by saying that stative verbs describe situations that are ...

: verbs that depict a state of being *

imperfective The imperfective (abbreviated or more ambiguously ) is a grammatical aspect used to describe ongoing, habitual, repeated, or similar semantic roles, whether that situation occurs in the past, present, or future. Although many languages have a gen ...

: verbs depicting ongoing, habitual or repeated action *

perfective The perfective aspect (abbreviated ), sometimes called the aoristic aspect, is a grammatical aspect that describes an action viewed as a simple whole; i.e., a unit without interior composition. The perfective aspect is distinguished from the imp ...

: verbs depicting a completed action or actions viewed as an entire process. Verbs have at least four

grammatical mood In linguistics, grammatical mood is a grammatical feature of verbs, used for signaling modality. That is, it is the use of verbal inflections that allow speakers to express their attitude toward what they are saying (for example, a statement of ...

s: *

indicative A realis mood (abbreviated ) is a grammatical mood which is used principally to indicate that something is a statement of fact; in other words, to express what the speaker considers to be a known state of affairs, as in declarative sentences. Most ...

: indicates that something is a statement of fact; in other words, to express what the speaker considers to be a known state of affairs, as in

declarative sentence In linguistics and grammar, a sentence is a linguistic expression, such as the English example "The quick brown fox jumps over the lazy dog." In traditional grammar, it is typically defined as a string of words that expresses a complete thought, ...

s. * imperative: forms commands or requests, including the giving of prohibition or permission, or any other kind of advice or exhortation. *

subjunctive The subjunctive (also known as conjunctive in some languages) is a grammatical mood, a feature of the utterance that indicates the speaker's attitude towards it. Subjunctive forms of verbs are typically used to express various states of unreality ...

: used to express various states of unreality such as wish, emotion, possibility, judgment, opinion, obligation, or action that has not yet occurred *

optative The optative mood ( or ; abbreviated ) is a grammatical mood that indicates a wish or hope regarding a given action. It is a superset of the cohortative mood and is closely related to the subjunctive mood but is distinct from the desiderative mo ...

: indicates a wish or hope. It is similar to the

cohortative mood In linguistics, hortative modalities (; abbreviated ) are verbal expressions used by the speaker to encourage or discourage an action. Different hortatives can be used to express greater or lesser intensity, or the speaker's attitude, for or a ...

and is closely related to the

subjunctive mood The subjunctive (also known as conjunctive in some languages) is a grammatical mood, a feature of the utterance that indicates the speaker's attitude towards it. Subjunctive forms of verbs are typically used to express various states of unreality ...

. Verbs had two

grammatical voice In linguistics, grammaticality is determined by the conformity to language usage as derived by the grammar of a particular speech variety. The notion of grammaticality rose alongside the theory of generative grammar, the goal of which is to form ...

s: *

active Active may refer to: Music * ''Active'' (album), a 1992 album by Casiopea * Active Records, a record label Ships * ''Active'' (ship), several commercial ships by that name * HMS ''Active'', the name of various ships of the British Royal ...

: used in a clause whose subject expresses the main verb's

agent Agent may refer to: Espionage, investigation, and law *, spies or intelligence officers * Law of agency, laws involving a person authorized to act on behalf of another ** Agent of record, a person with a contractual agreement with an insuranc ...

. *

mediopassive The mediopassive voice is a grammatical voice that subsumes the meanings of both the middle voice and the passive voice. Description Languages of the Indo-European family (and many others) typically have two or three of the following voices: acti ...

: for the

middle voice In grammar, the voice of a verb describes the relationship between the action (or state) that the verb expresses and the participants identified by its arguments (subject, object, etc.). When the subject is the agent or doer of the action, the ...

and the

passive voice A passive voice construction is a grammatical voice construction that is found in many languages. In a clause with passive voice, the grammatical subject expresses the ''theme'' or ''patient'' of the main verb – that is, the person or thing t ...

. Verbs had three

s: first, second and third. Verbs had three

grammatical number In linguistics, grammatical number is a grammatical category of nouns, pronouns, adjectives and verb agreement that expresses count distinctions (such as "one", "two" or "three or more"). English and other languages present number categories of ...

s: *singular * dual: referring to precisely two of the entities (objects or persons) identified by the noun or pronoun. *

plural The plural (sometimes abbreviated pl., pl, or ), in many languages, is one of the values of the grammatical category of number. The plural of a noun typically denotes a quantity greater than the default quantity represented by that noun. This de ...

: a number other than singular or dual. Verbs were probably marked by a highly developed system of

participle In linguistics, a participle () (from Latin ' a "sharing, partaking") is a nonfinite verb form that has some of the characteristics and functions of both verbs and adjectives. More narrowly, ''participle'' has been defined as "a word derived from ...

s, one for each combination of tense and voice, and an assorted array of

s and adjectival formations. The following table shows a possible reconstruction of the PIE verb endings from Sihler, which largely represents the current consensus among Indo-Europeanists.

Numbers

Proto-Indo-European numerals The numerals and derived numbers of the Proto-Indo-European language (PIE) have been reconstructed by modern linguists based on similarities found across all Indo-European languages. The following article lists and discusses their hypothesized for ...

are generally reconstructed as follows: Rather than specifically 100, * may originally have meant "a large number".

Particle

Proto-Indo-European particles The particles of the Proto-Indo-European language (PIE) have been reconstructed by modern linguists based on similarities found across all Indo-European languages. Adverbs Adverbs used as adpositions Many particles could be used both as adverbs ...

were probably used both as

adverb An adverb is a word or an expression that generally modifies a verb, adjective, another adverb, determiner, clause, preposition, or sentence. Adverbs typically express manner, place, time, frequency, degree, level of certainty, etc., answering ...

s and as

postpositions Prepositions and postpositions, together called adpositions (or broadly, in traditional grammar, simply prepositions), are a class of words used to express spatial or temporal relations (''in'', ''under'', ''towards'', ''before'') or mark various ...

. These postpositions became prepositions in most daughter languages. Reconstructed particles include for example, * "under, below"; the negators *, *; the conjunctions * "and", * "or" and others; and an

interjection An interjection is a word or expression that occurs as an utterance on its own and expresses a spontaneous feeling or reaction. It is a diverse category, encompassing many different parts of speech, such as exclamations ''(ouch!'', ''wow!''), curse ...

, *, expressing woe or agony.

Derivational morphology

Proto-Indo-European employed various means of deriving words from other words, or directly from verb roots.

Internal derivation

Internal derivation was a process that derived new words through changes in accent and ablaut alone. It was not as productive as external (affixing) derivation, but is firmly established by the evidence of various later languages.

=Possessive adjectives

= Possessive or associated adjectives were probably created from nouns through internal derivation. Such words could be used directly as adjectives, or they could be turned back into a noun without any change in morphology, indicating someone or something characterised by the adjective. They were probably also used as the second elements in compounds. If the first element was a noun, this created an adjective that resembled a present participle in meaning, e.g. "having much rice" or "cutting trees". When turned back into nouns, such compounds were

Bahuvrihi A ''bahuvrihi'' compound (from sa, बहुव्रीहि, tr=bahuvrīhi, lit=much rice/having much rice, originally referring to fertile land but later denoting the quality of being wealthy or rich) is a type of compound word that denotes ...

s or semantically resembled

agent noun In linguistics, an agent noun (in Latin, ) is a word that is derived from another word denoting an action, and that identifies an entity that does that action. For example, "driver" is an agent noun formed from the verb "drive". Usually, ''derive ...

s. In thematic stems, creating a possessive adjective seems to have involved shifting the accent one syllable to the right, for example: * ''*tómh₁-o-s'' "slice" (Greek ''tómos'') > ''*tomh₁-ó-s'' "cutting" (i.e. "making slices"; Greek ''tomós'') > ''*dr-u-tomh₁-ó-s'' "cutting trees" (Greek ''drutómos'' "woodcutter" with irregular accent). * ''*wólh₁-o-s'' "wish" (Sanskrit ''vára-'') > ''*wolh₁-ó-s'' "having wishes" (Sanskrit ''vará-'' "suitor"). In athematic stems, there was a change in the accent/ablaut class. The reconstructed four classes followed an ordering in which a derivation would shift the class one to the right: : acrostatic → proterokinetic → hysterokinetic → amphikinetic The reason for this particular ordering of the classes in derivation is not known. Some examples: * Acrostatic ''*krót-u-s'' ~ ''*krét-u-s'' "strength" (Sanskrit ''krátu-'') > proterokinetic ''*krét-u-s'' ~ ''*kr̥t-éw-s'' "having strength, strong" (Greek ''kratús''). * Hysterokinetic ''*ph₂-tḗr'' ~ ''*ph₂-tr-és'' "father" (Greek ''patḗr'') > amphikinetic ''*h₁su-péh₂-tōr'' ~ ''*h₁su-ph₂-tr-és'' "having a good father" (Greek ''εὑπάτωρ'', eupátōr).

=Vrddhi

= A vrddhi derivation, named after the Sanskrit grammatical term, signifying "of, belonging to, descended from". It was characterised by "upgrading" the root grade, from zero to full (''e'') or from full to lengthened (''ē''). When upgrading from zero to full grade, the vowel could sometimes be inserted in the "wrong" place, creating a different stem from the original full grade. Examples: * full grade ''*swéḱuro-s'' "father-in-law" (

) > lengthened grade *''swēḱuró-s'' "relating to one's father-in-law" (Vedic ,

Old High German Old High German (OHG; german: Althochdeutsch (Ahd.)) is the earliest stage of the German language, conventionally covering the period from around 750 to 1050. There is no standardised or supra-regional form of German at this period, and Old High ...

''swāgur'' "brother-in-law"). * full grade ''*dyḗw-s'' > zero grade ''*diw-és'' "sky" > new full grade ''*deyw-o-s'' "god,

sky god The sky often has important religious significance. Many religions, both polytheistic and monotheistic, have deities associated with the sky. The daytime sky deities are typically distinct from the nighttime ones. Stith Thompson's ''Motif-In ...

" (Vedic ,

''deus'', etc.). Note the difference in vowel placement, ''*dyew-'' in the full-grade stem of the original noun, but in the vrddhi derivative.

=Nominalization

= Adjectives with accent on the thematic vowel could be turned into nouns by moving the accent back onto the root. A zero grade root could remain so, or be "upgraded" to full grade like in a vrddhi derivative. Some examples: * PIE ''*ǵn̥h₁-tó-s'' "born" (Vedic ''jātá-'') > ''*ǵénh₁-to-'' "thing that is born" (German ''Kind''). * Greek ''leukós'' "white" > ''leũkos'' "a kind of fish", literally "white one". * Vedic ''kṛṣṇá-'' "dark" > ''kṛ́ṣṇa-'' "dark one", also "antelope". This kind of derivation is likely related to the possessive adjectives, and can be seen as essentially the reverse of it.

Affixal derivation

Syntax

The

syntax In linguistics, syntax () is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure ( constituency) ...

of the older Indo-European languages has been studied in earnest since at least the late nineteenth century, by such scholars as

Hermann Hirt Hermann Hirt (19 December 1865 in Magdeburg – 12 September 1936 in Gießen) was a German philologist and Indo-Europeanist. Biography Hirt wrote on German metres (''Untersuchungen zur westgermanischen Verskunst'', 1889), edited Schopenhauer's ...

and

Berthold Delbrück Berthold Gustav Gottlieb Delbrück (; 26 July 1842 – 3 January 1922) was a German linguist who devoted himself to the study of the comparative syntax of the Indo-European languages. Early life Delbrück was born in Putbus. He studied at the uni ...

. In the second half of the twentieth century, interest in the topic increased and led to reconstructions of Proto-Indo-European syntax. Since all the early attested IE languages were inflectional, PIE is thought to have relied primarily on morphological markers, rather than

word order In linguistics, word order (also known as linear order) is the order of the syntactic constituents of a language. Word order typology studies it from a cross-linguistic perspective, and examines how different languages employ different orders. C ...

, to signal

syntactic In linguistics, syntax () is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure (constituency), ...

relationships within sentences. Still, a default (

unmarked In linguistics and social sciences, markedness is the state of standing out as nontypical or divergent as opposed to regular or common. In a marked–unmarked relation, one term of an opposition is the broader, dominant one. The dominant defau ...

) word order is thought to have existed in PIE. In 1892,

Jacob Wackernagel Jacob Wackernagel (11 December 1853 – 22 May 1938) was a Swiss linguist, Indo-Europeanist and scholar of Sanskrit. He was born in Basel, son of the philologist Wilhelm Wackernagel (1806–1869). Biography Jacob Wackernagel was born on 11 ...

reconstructed PIE's word order as subject–verb–object (SVO), based on evidence in Vedic Sanskrit.

Winfred P. Lehmann Winfred Philip Lehmann (June 23, 1916August 1, 2007) was an American linguist who specialized in historical, Germanic, and Indo-European linguistics. He was for many years a professor and head of departments for linguistics at the University of ...

(1974), on the other hand, reconstructs PIE as a

subject–object–verb Subject ( la, subiectus "lying beneath") may refer to: Philosophy *'' Hypokeimenon'', or ''subiectum'', in metaphysics, the "internal", non-objective being of a thing **Subject (philosophy), a being that has subjective experiences, subjective con ...

(SOV) language. He posits that the presence of person marking in PIE verbs motivated a shift from OV to VO order in later dialects. Many of the descendant languages have VO order: modern Greek,

and

Albanian Albanian may refer to: *Pertaining to Albania in Southeast Europe; in particular: **Albanians, an ethnic group native to the Balkans **Albanian language **Albanian culture **Demographics of Albania, includes other ethnic groups within the country ...

prefer SVO,

Insular Celtic Insular Celtic languages are the group of Celtic languages of Brittany, Great Britain, Ireland, and the Isle of Man. All surviving Celtic languages are in the Insular group, including Breton, which is spoken on continental Europe in Brittany, ...

has VSO as the default order, and even the

Anatolian languages The Anatolian languages are an extinct branch of Indo-European languages that were spoken in Anatolia, part of present-day Turkey. The best known Anatolian language is Hittite, which is considered the earliest-attested Indo-European language. ...

show some signs of this word order shift. Tocharian and Indo-Iranian, meanwhile, retained the conservative OV order. Lehmann attributes the context-dependent order preferences in Baltic, Slavic and Germanic to outside influences.

Donald Ringe Donald "Don" Ringe () is an American linguist and Indo-Europeanist. Ringe graduated from University of Kentucky and then received a Master of Philosophy in Linguistics as a Marshall Scholar from the University of Oxford. He received Ph.D in lin ...

(2006), however, attributes these to internal developments instead. Paul Friedrich (1975) disagrees with Lehmann's analysis. He reconstructs PIE with the following syntax: * basic SVO word order * adjectives before nouns * head nouns before genitives *

prepositions Prepositions and postpositions, together called adpositions (or broadly, in traditional grammar, simply prepositions), are a class of words used to express spatial or temporal relations (''in'', ''under'', ''towards'', ''before'') or mark various ...

rather than postpositions * no dominant order in comparative constructions * main clauses before

relative clauses A relative clause is a clause that modifies a noun or noun phraseRodney D. Huddleston, Geoffrey K. Pullum, ''A Student's Introduction to English Grammar'', CUP 2005, p. 183ff. and uses some grammatical device to indicate that one of the arguments ...

Friedrich notes that even among those Indo-European languages with basic OV word order, none of them are ''rigidly'' OV. He also notes that these non-rigid OV languages mainly occur in parts of the IE area that overlap with OV languages from other families (such as

Uralic The Uralic languages (; sometimes called Uralian languages ) form a language family of 38 languages spoken by approximately 25million people, predominantly in Northern Eurasia. The Uralic languages with the most native speakers are Hungarian (w ...

and Dravidian), whereas VO is predominant in the central parts of the IE area. For these reasons, among others, he argues for a VO common ancestor.

Hans Henrich Hock Hans Henrich Hock (born 26 September 1938) is Professor Emeritus of Linguistics and Sanskrit at the University of Illinois Urbana-Champaign. Hock holds a PhD in linguistics from Yale University. His research interests include general historical ...

(2015) reports that the SVO hypothesis still has some adherents, but the "broad consensus" among PIE scholars is that PIE would have been an SOV language. The SOV default word order with other orders used to express emphasis (e.g.,

verb–subject–object A verb () is a word (part of speech) that in syntax generally conveys an action (''bring'', ''read'', ''walk'', ''run'', ''learn''), an occurrence (''happen'', ''become''), or a state of being (''be'', ''exist'', ''stand''). In the usual descri ...

to emphasise the verb) is attested in

Old Indo-Aryan The Indo-Aryan languages (or sometimes Indic languages) are a branch of the Indo-Iranian languages in the Indo-European language family. As of the early 21st century, they have more than 800 million speakers, primarily concentrated in India, Pa ...

Old Iranian The Iranian languages or Iranic languages are a branch of the Indo-Iranian languages in the Indo-European languages, Indo-European language family that are spoken natively by the Iranian peoples, predominantly in the Iranian plateau, Iranian Pl ...

Old Latin Old Latin, also known as Early Latin or Archaic Latin (Classical la, prīsca Latīnitās, lit=ancient Latinity), was the Latin language in the period before 75 BC, i.e. before the age of Classical Latin. It descends from a common Proto-Italic ...

and Hittite, while traces of it can be found in the

personal pronouns of the

In popular culture

The

Ridley Scott Sir Ridley Scott (born 30 November 1937) is a British film director and producer. Directing, among others, science fiction films, his work is known for its atmospheric and highly concentrated visual style. Scott has received many accolades thr ...

film ''

Prometheus In Greek mythology, Prometheus (; , , possibly meaning "forethought")Smith"Prometheus". is a Titan god of fire. Prometheus is best known for defying the gods by stealing fire from them and giving it to humanity in the form of technology, know ...

'' features an android named David (played by

Michael Fassbender Michael Fassbender (born 2 April 1977) is an Irish actor. He is the recipient of various accolades, including a Screen Actors Guild Award, a Critics' Choice Movie Award, and nominations for two Academy Awards, four British Academy Film Award ...

) who learns Proto-Indo-European to communicate with the Engineer, an extraterrestrial whose race may have created humans. David practices PIE by reciting

Schleicher's fable Schleicher's fable is a text composed in a reconstructed version of the Proto-Indo-European (PIE) language, published by August Schleicher in 1868. Schleicher was the first scholar to compose a text in PIE. The fable is entitled ("The Sheep weand ...

. Linguist Dr Anil Biltoo created the film's reconstructed dialogue and had an onscreen role teaching David Schleicher's fable. The 2016 video game ''

Far Cry Primal ''Far Cry Primal'' is a 2016 action-adventure game developed by Ubisoft Montreal and published by Ubisoft. It is a spin-off to ''Far Cry 4'', and the tenth overall installment in the ''Far Cry'' series. Set during prehistoric times, the game fol ...

'', set in around 10,000 BC, features dialects of an

invented language A constructed language (sometimes called a conlang) is a language whose phonology, grammar, and vocabulary, instead of having developed natural language, naturally, are consciously devised for some purpose, which may include being devised for a ...

based partly on PIE, intended to be its fictional predecessor. Linguists constructed three dialects—Wenja, Udam and Izila—one for each of the three featured tribes.

Notes

References

Bibliography

* * * * * * * *

External links

* At the University of Texas Linguistic Research Center
List of online books

Indo-European Lexicon

Proto-Indo-European Lexicon
at the University of Helsinki, Department of Modern Languages, Department of World Cultures, Indo-European Studies *
Indo-European Grammar, Syntax & Etymology Dictionary

Indo-European Lexical Cognacy Database

an online collection of video lectures on Ancient Indo-European languages {{DEFAULTSORT:Proto-Indo-European Language Bronze Age Indo-European languages

Language Language is a structured system of communication. The structure of a language is its grammar and the free components are its vocabulary. Languages are the primary means by which humans communicate, and may be conveyed through a variety of met ...

Indo-European The Indo-European languages are a language family native to the overwhelming majority of Europe, the Iranian plateau, and the northern Indian subcontinent. Some European languages of this family, English, French, Portuguese, Russian, Dutch ...