Alpha (uppercase , lowercase ; grc, ἄλφα, ''álpha'', or ell, άλφα, álfa) is the first letter of the

Greek alphabet The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BCE. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as ...

. In the system of

Greek numerals Greek numerals, also known as Ionic, Ionian, Milesian, or Alexandrian numerals, are a system of writing numbers using the letters of the Greek alphabet. In modern Greece, they are still used for ordinal numbers and in contexts similar to those ...

, it has a value of one. Alpha is derived from the Phoenician letter

aleph Aleph (or alef or alif, transliterated ʾ) is the first letter of the Semitic abjads, including Phoenician , Hebrew , Aramaic , Syriac , Arabic ʾ and North Arabian 𐪑. It also appears as South Arabian 𐩱 and Ge'ez . These let ...

, which is the

West Semitic The West Semitic languages are a proposed major sub-grouping of ancient Semitic languages. The term was first coined in 1883 by Fritz Hommel.ox". Letters that arose from alpha include the

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 ...

letter A and the Cyrillic letter А.

Uses

Greek

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 p ...

, alpha was pronounced and could be either phonemically long ( ː or short ( . Where there is ambiguity, long and short alpha are sometimes written with a

macron Macron may refer to: People * Emmanuel Macron (born 1977), president of France since 2017 ** Brigitte Macron (born 1953), French teacher, wife of Emmanuel Macron * Jean-Michel Macron (born 1950), French professor of neurology, father of Emmanu ...

and

breve A breve (, less often , neuter form of the Latin "short, brief") is the diacritic mark ˘, shaped like the bottom half of a circle. As used in Ancient Greek, it is also called , . It resembles the caron (the wedge or in Czech, in ...

today: Ᾱᾱ, Ᾰᾰ. * ὥρα = ὥρᾱ ''hōrā'' "a time" * γλῶσσα = γλῶσσᾰ ''glôssa'' "tongue" In

Modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers simply as Greek (, ), refers collectively to the dialects of the Greek language spoken in the modern era, including the official standardized form of the ...

vowel length In linguistics, vowel length is the perceived length of a vowel sound: the corresponding physical measurement is duration. In some languages vowel length is an important phonemic factor, meaning vowel length can change the meaning of the word ...

has been lost, and all instances of alpha simply represent the

open front unrounded vowel The open front unrounded vowel, or low front unrounded vowel, is a type of vowel sound used in some spoken languages. It is one of the eight primary cardinal vowels, not directly intended to correspond to a vowel sound of a specific language b ...

. In the

polytonic Greek orthography has used a variety of diacritics starting in the Hellenistic period. The more complex polytonic orthography ( el, πολυτονικό σύστημα γραφής, translit=polytonikó sýstīma grafī́s), which includes fiv ...

orthography of Greek, alpha, like other vowel letters, can occur with several diacritic marks: any of three accent symbols (), and either of two breathing marks (), as well as combinations of these. It can also combine with the

iota subscript The iota subscript is a diacritic mark in the Greek alphabet shaped like a small vertical stroke or miniature iota placed below the letter. It can occur with the vowel letters eta , omega , and alpha . It represents the former presence of an ...

().

Greek grammar

In the

Attic An attic (sometimes referred to as a ''loft'') is a space found directly below the pitched roof of a house or other building; an attic may also be called a ''sky parlor'' or a garret. Because attics fill the space between the ceiling of the ...

– Ionic dialect of Ancient Greek, long alpha fronted to (

eta Eta (uppercase , lowercase ; grc, ἦτα ''ē̂ta'' or ell, ήτα ''ita'' ) is the seventh letter of the Greek alphabet, representing the close front unrounded vowel . Originally denoting the voiceless glottal fricative in most dialects, ...

). In Ionic, the shift took place in all positions. In Attic, the shift did not take place after epsilon,

iota Iota (; uppercase: Ι, lowercase: ι; ) is the ninth letter of the Greek alphabet. It was derived from the Phoenician letter Yodh. Letters that arose from this letter include the Latin I and J, the Cyrillic І (І, і), Yi (Ї, ї), and ...

, and

rho Rho (uppercase Ρ, lowercase ρ or ; el, ρο or el, ρω, label=none) is the 17th letter of the Greek alphabet. In the system of Greek numerals it has a value of 100. It is derived from Phoenician letter res . Its uppercase form uses the sa ...

(ε, ι, ρ; ''e'', ''i'', ''r''). In Doric and

Aeolic In linguistics, Aeolic Greek (), also known as Aeolian (), Lesbian or Lesbic dialect, is the set of dialects of Ancient Greek spoken mainly in Boeotia; in Thessaly; in the Aegean island of Lesbos; and in the Greek colonies of Aeolis in Anato ...

, long alpha is preserved in all positions. *Doric, Aeolic, Attic ''chṓrā'' – Ionic ''chṓrē'', "country" *Doric, Aeolic ''phā́mā'' – Attic, Ionic ''phḗmē'', "report" Privative a is the

prefix ἀ- or ἀν- ''a-'', ''an-'', added to words to negate them. It originates from the

Proto-Indo-European Proto-Indo-European (PIE) is the reconstructed common ancestor of the Indo-European language family. Its proposed features have been derived by linguistic reconstruction from documented Indo-European languages. No direct record of Proto-Indo- ...

*' ( syllabic nasal) and is

cognate In historical linguistics, cognates or lexical cognates are sets of words in different languages that have been inherited in direct descent from an etymological ancestor in a common parent language. Because language change can have radical e ...

with English ''un-''. Copulative a is the Greek prefix ἁ- or ἀ- ''ha-'', ''a-''. It comes from Proto-Indo-European *'.

Mathematics and science

The letter alpha represents various concepts in

physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which rel ...

and chemistry, including

alpha radiation Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or 'decays' into a different atomic nucleus, with a mass number that is reduced by four and an atomi ...

, angular acceleration,

alpha particle Alpha particles, also called alpha rays or alpha radiation, consist of two protons and two neutrons bound together into a particle identical to a helium-4 nucleus. They are generally produced in the process of alpha decay, but may also be pro ...

s, alpha carbon and strength of

electromagnetic interaction In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions o ...

(as

Fine-structure constant In physics, the fine-structure constant, also known as the Sommerfeld constant, commonly denoted by (the Greek letter ''alpha''), is a fundamental physical constant which quantifies the strength of the electromagnetic interaction between ele ...

). Alpha also stands for thermal expansion coefficient of a compound in

physical chemistry Physical chemistry is the study of macroscopic and microscopic phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical ...

. It is also commonly used in mathematics in algebraic solutions representing quantities such as angles. Furthermore, in mathematics, the letter alpha is used to denote the area underneath a

normal curve In statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable. The general form of its probability density function is : f(x) = \frac e^ The parameter \mu is ...

in statistics to denote

significance level In statistical hypothesis testing, a result has statistical significance when it is very unlikely to have occurred given the null hypothesis (simply by chance alone). More precisely, a study's defined significance level, denoted by \alpha, is the p ...

when proving null and alternative hypotheses. In

ethology Ethology is the scientific study of animal behaviour, usually with a focus on behaviour under natural conditions, and viewing behaviour as an evolutionarily adaptive trait. Behaviourism as a term also describes the scientific and objective ...

, it is used to name the dominant individual in a group of animals. In aerodynamics, the letter is used as a symbol for the

angle of attack In fluid dynamics, angle of attack (AOA, α, or \alpha) is the angle between a reference line on a body (often the chord line of an airfoil) and the vector representing the relative motion between the body and the fluid through which it is ...

of an aircraft and the word "alpha" is used as a synonym for this property. In

mathematical logic Mathematical logic is the study of formal logic within mathematics. Major subareas include model theory, proof theory, set theory, and recursion theory. Research in mathematical logic commonly addresses the mathematical properties of formal ...

, α is sometimes used as a placeholder for ordinal numbers. The proportionality operator "

∝ In mathematics, two sequences of numbers, often experimental data, are proportional or directly proportional if their corresponding elements have a constant ratio, which is called the coefficient of proportionality or proportionality constant ...

" (in

Unicode Unicode, formally The Unicode Standard,The formal version reference is is an information technology standard for the consistent encoding, representation, and handling of text expressed in most of the world's writing systems. The standard, ...

: U+221D) is sometimes mistaken for alpha. The uppercase letter alpha is not generally used as a symbol because it tends to be rendered identically to the uppercase Latin A.

International Phonetic Alphabet

In the International Phonetic Alphabet, the letter ɑ, which looks similar to the lower-case alpha, represents the

open back unrounded vowel The open back unrounded vowel, or low back unrounded vowel, is a type of vowel sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , and the equivalent X-SAMPA symbol is A. The ...

History and symbolism

Origin

The

Phoenician alphabet The Phoenician alphabet is an alphabet (more specifically, an abjad) known in modern times from the Canaanite and Aramaic inscriptions found across the Mediterranean region. The name comes from the Phoenician civilization. The Phoenician a ...

was adopted for Greek in the early 8th century BC, perhaps in

Euboea Evia (, ; el, Εύβοια ; grc, Εὔβοια ) or Euboia (, ) is the second-largest Greek island in area and population, after Crete. It is separated from Boeotia in mainland Greece by the narrow Euripus Strait (only at its narrowest ...

. The majority of the letters of the Phoenician alphabet were adopted into Greek with much the same sounds as they had had in Phoenician, but '' ʼāleph'', the Phoenician letter representing the glottal stop , was adopted as representing the vowel ; similarly, '' hē'' and '' ʽayin'' are Phoenician consonants that became Greek vowels, epsilon and

omicron Omicron (; uppercase Ο, lowercase ο, ell, όμικρον) is the 15th letter of the Greek alphabet. This letter is derived from the Phoenician letter ayin: . In classical Greek, omicron represented the close-mid back rounded vowel in contr ...

, respectively.

Plutarch

Plutarch Plutarch (; grc-gre, Πλούταρχος, ''Ploútarchos''; ; – after AD 119) was a Greek Middle Platonist philosopher, historian, biographer, essayist, and priest at the Temple of Apollo in Delphi. He is known primarily for his ...

, in ''

Moralia The ''Moralia'' ( grc, Ἠθικά ''Ethika''; loosely translated as "Morals" or "Matters relating to customs and mores") is a group of manuscripts dating from the 10th–13th centuries, traditionally ascribed to the 1st-century Greek scholar Plu ...

'', presents a discussion on why the letter alpha stands first in the alphabet. Ammonius asks Plutarch what he, being a

Boeotia Boeotia ( ), sometimes Latinisation of names, Latinized as Boiotia or Beotia ( el, wikt:Βοιωτία, Βοιωτία; modern Greek, modern: ; ancient Greek, ancient: ), formerly known as Cadmeis, is one of the regional units of Greece. It is pa ...

n, has to say for

Cadmus In Greek mythology, Cadmus (; grc-gre, Κάδμος, Kádmos) was the legendary Phoenician founder of Boeotian Thebes. He was the first Greek hero and, alongside Perseus and Bellerophon, the greatest hero and slayer of monsters before the ...

, the

Phoenicia Phoenicia () was an ancient thalassocratic civilization originating in the Levant region of the eastern Mediterranean, primarily located in modern Lebanon. The territory of the Phoenician city-states extended and shrank throughout their his ...

n who reputedly settled in Thebes and introduced the alphabet to Greece, placing ''alpha'' first because it is the Phoenician name for ox—which, unlike

Hesiod Hesiod (; grc-gre, Ἡσίοδος ''Hēsíodos'') was an ancient Greek poet generally thought to have been active between 750 and 650 BC, around the same time as Homer. He is generally regarded by western authors as 'the first written poet i ...

, the Phoenicians considered not the second or third, but the first of all necessities. "Nothing at all," Plutarch replied. He then added that he would rather be assisted by

Lamprias Lamprias (Greek: Λαμπρίας) was Plutarch's grandfather as he attested in ''Moralia'',''Symposiacs'', Book IX, questions II and IIIonline text at Adelaide library) and in his Life of Antony. According to Plutarch, Lamprias was a man of eloqu ...

, his own grandfather, than by

Dionysus In ancient Greek religion and myth, Dionysus (; grc, Διόνυσος ) is the god of the grape-harvest, winemaking, orchards and fruit, vegetation, fertility, insanity, ritual madness, religious ecstasy, festivity, and theatre. The Romans ...

' grandfather, i.e. Cadmus. For Lamprias had said that the first articulate sound made is "alpha", because it is very plain and simple—the air coming off the mouth does not require any motion of the tongue—and therefore this is the first sound that children make. According to Plutarch's natural order of attribution of the

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 (l ...

s to the

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a ...

s, alpha was connected with the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width ...

Alpha and Omega

As the first letter of the alphabet, Alpha as a

Greek numeral Greek numerals, also known as Ionic, Ionian, Milesian, or Alexandrian numerals, are a system of writing numbers using the letters of the Greek alphabet. In modern Greece, they are still used for ordinal numbers and in contexts similar to those ...

came to represent the number 1. Therefore, Alpha, both as a symbol and term, is used to refer to the "first", or "primary", or "principal" (most significant) occurrence or status of a thing. The New Testament has God declaring himself to be the "Alpha and Omega, the beginning and the end, the first and the last." (

Revelation In religion and theology, revelation is the revealing or disclosing of some form of truth or knowledge through communication with a deity or other supernatural entity or entities. Background Inspiration – such as that bestowed by God on th ...

22:13, KJV, and see also 1:8). Consequently, the term "alpha" has also come to be used to denote "primary" position in social hierarchy, examples being "

alpha males In biology, a dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social groups interact, creating a ranking system. A dominant higher-ranking individual is s ...

" or pack leaders.

Computer encodings

* Greek alpha / Coptic alfa For accented Greek characters, see Greek diacritics: Computer encoding. *

IPA IPA commonly refers to: * India pale ale, a style of beer * International Phonetic Alphabet, a system of phonetic notation * Isopropyl alcohol, a chemical compound IPA may also refer to: Organizations International * Insolvency Practitioner ...

alpha * Mathematical / Technical alpha

References

{{reflist Greek letters Vowel letters