Upsilon (, ;
uppercase Υ, lowercase υ; el, ''ýpsilon'' ) or ypsilon
is the 20th 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 we ...
. 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 tho ...
, grc, Υʹ, label=none has a value of 400. It is derived from the
Phoenician waw
Waw or WAW may refer to:
* Waw (letter), a letter in many Semitic abjads
* Waw, the velomobile
* Another spelling for the town Wau, South Sudan
* Waw Township, Burma
*Warsaw Chopin Airport, an international airport serving Warsaw, Poland (IATA ai ...
.
Etymology
The name of the letter was originally just "υ" (''y;'' also called ''hy'', hence "
hyoid
The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical vertebra. ...
", meaning "shaped like the letter υ"), but the name changed to "υ ψιλόν" ''u psilon'' 'simple u' to distinguish it from οι, which had come to have the same pronunciation.
Pronunciation
In early
Attic Greek
Attic Greek is the Greek language, Greek dialect of the regions of ancient Greece, ancient region of Attica, including the ''polis'' of classical Athens, Athens. Often called classical Greek, it was the prestige (sociolinguistics), prestige diale ...
(6th century BCE), it was pronounced (a
close back rounded vowel
The close back rounded vowel, or high back rounded vowel, is a type of vowel sound used in many spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , and the equivalent X-SAMPA symbol is u.
In ...
like the English "long o͞o"). In
Classical 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 ...
, it was pronounced (a
close front rounded vowel
The close front rounded vowel, or high front rounded vowel, is a type of vowel sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is /y/, and the equivalent X-SAMPA symbol is y. Acr ...
), at least until 1030. 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 ...
, it is pronounced ; in the
digraphs and , as or ; and in the digraph as . In ancient Greek, it occurred in both
long and short versions, but Modern Greek does not have a length distinction.
As an initial letter in Classical Greek, it always carried the
rough breathing
In the polytonic orthography of Ancient Greek, the rough breathing ( grc, δασὺ πνεῦμα, dasỳ pneûma or ''daseîa''; la, spīritus asper) character is a diacritical mark used to indicate the presence of an sound before a vowel, d ...
(equivalent to ''h'') as reflected in the many
Greek-derived English words, such as those that begin with ''hyper-'' and ''hypo-''. This rough breathing was derived from an older pronunciation that used a
sibilant
Sibilants are fricative consonants of higher amplitude and pitch, made by directing a stream of air with the tongue towards the teeth. Examples of sibilants are the consonants at the beginning of the English words ''sip'', ''zip'', ''ship'', and ...
instead; this sibilant was not lost in Latin, giving rise to such cognates as ''super-'' (for ''hyper-'') and ''sub-'' (for ''hypo-'').
Upsilon participated as the second element in
falling diphthong
A diphthong ( ; , ), also known as a gliding vowel, is a combination of two adjacent vowel sounds within the same syllable. Technically, a diphthong is a vowel with two different targets: that is, the tongue (and/or other parts of the speech ...
s, which have subsequently developed in various ways.
Correspondence with Latin Y
![Y-like European letters](https://upload.wikimedia.org/wikipedia/commons/c/c9/Y-like_European_letters.svg)
The usage of
Y in Latin dates back to the first century BC. It was used to transcribe loanwords from Greek, so it was not a native sound of Latin and was usually pronounced or . The latter pronunciation was the most common in the Classical period and was used mostly by uneducated people. The
Roman Emperor Claudius
Tiberius Claudius Caesar Augustus Germanicus (; 1 August 10 BC – 13 October AD 54) was the fourth Roman emperor, ruling from AD 41 to 54. A member of the Julio-Claudian dynasty, Claudius was born to Nero Claudius Drusus, Drusu ...
proposed introducing a
new letter into the
Latin alphabet
The Latin alphabet or Roman alphabet is the collection of letters originally used by the ancient Romans to write the Latin language. Largely unaltered with the exception of extensions (such as diacritics), it used to write English and the o ...
to transcribe the so-called ''sonus medius'' (a short vowel before labial consonants), but in inscriptions, the new letter was sometimes used for Greek upsilon instead.
Four letters of the
Latin alphabet
The Latin alphabet or Roman alphabet is the collection of letters originally used by the ancient Romans to write the Latin language. Largely unaltered with the exception of extensions (such as diacritics), it used to write English and the o ...
arose from it: and
U ,
Y and, much later,
V and
W. In the
Cyrillic script
The Cyrillic script ( ), Slavonic script or the Slavic script, is a writing system used for various languages across Eurasia. It is the designated national script in various Slavic languages, Slavic, Turkic languages, Turkic, Mongolic languages, ...
, the letters
U (У, у) and
izhitsa
Izhitsa or Izhica (Ѵ, ѵ; italics: ; OCS: Ѷжица, Russian: Ижица, Ukrainian: Іжиця) is a letter of the early Cyrillic alphabet and several later alphabets, usually the last in the row. It originates from the Greek letter upsilon ...
(Ѵ, ѵ) arose from it.
In some languages, including
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
**Ge ...
and
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 ...
, the name ''upsilon'' (''Ypsilon'' in German, ''ípsilon'' in Portuguese) is used to refer to the Latin letter Y as well as the Greek letter. In some other languages, the (Latin) Y is referred to as a "Greek I" (''i griega'' in
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, Can ...
, ''i grec'' in
French), also noting its Greek origin.
Usage
* In
particle physics
Particle physics or high energy physics is the study of fundamental particles and forces that constitute matter and radiation. The fundamental particles in the universe are classified in the Standard Model as fermions (matter particles) an ...
the capital Greek letter ϒ denotes an
Upsilon particle
The Upsilon meson () is a quarkonium state (i.e. Flavour (particle physics), flavourless meson) formed from a bottom quark and its antiparticle. It was discovered by the E288 experiment team, headed by Leon Lederman, at Fermilab in 1977, and was t ...
. Note that the symbol should always look like
in order to avoid confusion with a Latin Y denoting the
hypercharge
In particle physics, the hypercharge (a portmanteau of hyperon, hyperonic and charge (physics), charge) ''Y'' of a subatomic particle, particle is a quantum number conserved under the strong interaction. The concept of hypercharge provides a sin ...
. This may be done either with a font such as FreeSerif or with the dedicated Unicode character U+03D2 ϒ.
* Automobile manufacturer
Lancia
Lancia () is an Italian car manufacturer and a subsidiary of FCA Italy S.p.A., which is currently a Stellantis division. The present legal entity of Lancia was formed in January 2007 when its corporate parent reorganised its businesses, but it ...
has a model called the Ypsilon. See
Lancia Ypsilon
The Lancia Ypsilon is a supermini manufactured and marketed by Lancia, now in its third generation and as of 2022, the marque's only model. The Ypsilon was released in 1995, as a larger and more expensive replacement to the Y10. Between 1995 a ...
.
* In the
International Phonetic Alphabet
The International Phonetic Alphabet (IPA) is an alphabetic system of phonetic transcription, phonetic notation based primarily on the Latin script. It was devised by the International Phonetic Association in the late 19th century as a standa ...
, the symbol is used to represent a
labiodental approximant
The voiced labiodental approximant is a type of consonantal sound, used in some spoken languages. It is something between an English / w/ and / v/, pronounced with the teeth and lips held in the position used to articulate the letter V. The sym ...
.
* In
astrophysics
Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline said, Astrophysics "seeks to ascertain the nature of the h ...
and
physical cosmology
Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of f ...
, ϒ refers to the
mass-to-light ratio In astrophysics and physical cosmology the mass-to-light ratio, normally designated with the Greek letter upsilon, , is the quotient between the total mass of a spatial volume (typically on the scales of a galaxy or a cluster) and its luminosity. T ...
.
* In
statistics
Statistics (from German language, German: ''wikt:Statistik#German, Statistik'', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of ...
, it is sometimes used instead of v or nu to indicate
degrees of freedom
Similar appearance
* A similar symbol
![Aries](https://upload.wikimedia.org/wikipedia/commons/5/5e/Aries.svg)
(Unicode ♈ U+2648) is used for the
astrological sign
In Western astrology, astrological signs are the twelve 30-degree sectors that make up Earth's 360-degree orbit around the Sun. The signs enumerate from the first day of spring, known as the First Point of Aries, which is the vernal equinox. ...
of
Aries
Aries may refer to:
*Aries (astrology), an astrological sign
*Aries (constellation), a constellation of stars in the zodiac
Arts, entertainment and media
* ''Aries'' (album), by Luis Miguel, 1993
* ''Aries'' (EP), by Alice Chater, 2020
* "Aries" ...
.
Symbolism
![Geoffrey Tory Ypsilon](https://upload.wikimedia.org/wikipedia/commons/a/a3/Geoffrey_Tory_Ypsilon.jpg)
Upsilon is known as Pythagoras' letter, or the Samian letter, because
Pythagoras
Pythagoras of Samos ( grc, Πυθαγόρας ὁ Σάμιος, Pythagóras ho Sámios, Pythagoras the Samos, Samian, or simply ; in Ionian Greek; ) was an ancient Ionians, Ionian Ancient Greek philosophy, Greek philosopher and the eponymou ...
used it as an emblem of the path of virtue or vice. As the Roman writer
Persius
Aulus Persius Flaccus (; 4 December 3424 November 62 AD) was a Ancient Rome, Roman poet and satirist of Etruscan civilization, Etruscan origin. In his works, poems and satires, he shows a Stoicism, Stoic wisdom and a strong criticism for what he ...
wrote in ''Satire III'':
Lactantius
Lucius Caecilius Firmianus Lactantius (c. 250 – c. 325) was an early Christian author who became an advisor to Roman emperor, Constantine I, guiding his Christian religious policy in its initial stages of emergence, and a tutor to his son Cr ...
, an early Christian author (ca. 240 – ca. 320), refers to this:
Character encodings
* Greek Upsilon
[Unicode Code Charts]
Greek and Coptic (Range: 0370-03FF)
/ref>
* Coptic Ua
* Latin Upsilon
* Mathematical Upsilon
These characters are used only as mathematical symbols. Stylized Greek text should be encoded using the normal Greek letters, with markup and formatting to indicate text style.
Notes
External links
* {{cite web, last=Merrifield, first=Michael, title=Υ – Mass to Light Ratio, url=http://www.sixtysymbols.com/videos/masstolight.htm, work=Sixty Symbols, publisher=Brady Haran
Brady John Haran (born 18 June 1976) is an Australian-British independent filmmaker and video journalist who produces educational videos and documentary films for his YouTube channels, the most notable being ''Periodic Videos'' and '' Numbe ...
for the University of Nottingham
The University of Nottingham is a public university, public research university in Nottingham, United Kingdom. It was founded as University College Nottingham in 1881, and was granted a royal charter in 1948. The University of Nottingham belongs t ...
, year=2009
Greek letters
Vowel letters