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From Wikipedia, the free encyclopedia

Third letter of the Greek alphabet

Not to be confused with the Latin letterY, the Cyrillic letterУ, or the Church Slavonic Cyrillic letterꙊ.

This article is about the Greek letter GammaΓ (andγ) as used in various fields. For the Latin forms likeƔ seeGamma § Phonetic transcription. For other uses, seeGamma (disambiguation).

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Αα	Alpha	Νν	Nu
Ββ	Beta	Ξξ	Xi
Γγ	Gamma	Οο	Omicron
Δδ	Delta	Ππ	Pi
Εε	Epsilon	Ρρ	Rho
Ζζ	Zeta	Σσς	Sigma
Ηη	Eta	Ττ	Tau
Θθ	Theta	Υυ	Upsilon
Ιι	Iota	Φφ	Phi
Κκ	Kappa	Χχ	Chi
Λλ	Lambda	Ψψ	Psi
Μμ	Mu	Ωω	Omega

Archaic local variants

Ϝ	Digamma	Ͱ	Heta
Ϻ	San	Ϙ	Koppa
Ͷ	Tsan Digamma	Ͳ	Sampi

Diacritics and other symbols

ϗ
ϛ

Numerals (Attic)

Related topics

Category

v
t
e

Gamma (/ˈɡæmə/ ^ⓘ;^[1] uppercaseΓ, lowercaseγ;Greek:γάμμα,romanized: gámma) is the third letter of theGreek alphabet. In the system ofGreek numerals it has a value of 3. InAncient Greek, the letter gamma represented avoiced velar stopIPA:[ɡ]. InModern Greek, this letter normally represents avoiced velar fricativeIPA:[ɣ], except before either of the twofront vowels (/e/, /i/), where it represents avoiced palatal fricativeIPA:[ʝ]; while /g/ in foreign words is instead commonly transcribed as γκ).

In theInternational Phonetic Alphabet and other modern Latin-alphabet basedphonetic notations, it represents the voiced velar fricative.

History

Further information:History of the Greek alphabet

The Greek letter Gamma Γ is a grapheme derived from thePhoenician letter𐤂‎ (gīml) which was rotated from theright-to-left script of Canaanite to accommodate the Greek language's writing system of left-to-right. The Canaanitegrapheme represented the /g/ phoneme in theCanaanite language, and as such is cognate withgimel ג of theHebrew alphabet.

Based on its name, the letter has been interpreted as an abstract representation of acamel's neck,^[2] but this has been criticized as contrived,^[3] and it is more likely that the letter is derived from an Egyptian hieroglyph representing a club orthrowing stick.^[4]

The alphabet onblack-figure pottery with alambda-shaped gamma

InArchaic Greece, the shape of gamma was closer to a classicallambda (Λ), while lambda retained the PhoenicianL-shape (𐌋‎).

Letters that arose from the Greek gamma includeEtruscan (Old Italic) 𐌂,Roman C andG,Runickaunanᚲ,Gothicgeuua𐌲, theCoptic Ⲅ, and theCyrillic lettersГ andҐ.^[5]

Greek phoneme

Further information:Ancient Greek phonology andModern Greek phonology

The Ancient Greek /g/ phoneme was the voiced velar stop, continuing the reconstructedproto-Indo-European*g,*ǵ.

The modern Greek phoneme represented by gamma is realized either as avoiced palatal fricative (/ʝ/) before afront vowel (/e/, /i/), or as avoiced velar fricative/ɣ/ in all other environments. Both in Ancient and in Modern Greek, before othervelar consonants (κ, χ, ξ – that is,k, kh, ks), gamma represents avelar nasal/ŋ/. A double gamma γγ (e.g., άγγελος, "angel") represents the sequence/ŋɡ/ (phonetically varying[ŋɡ~ɡ]) or/ŋɣ/.

Phonetic transcription

Lowercase Greek gamma is used in theAmericanist phonetic notation andUralic Phonetic Alphabet to indicate voiced consonants.

The gamma was also added to the Latin alphabet, asLatin gamma, in the following forms:majuscule Ɣ,minuscule ɣ, and superscript modifier letter ˠ.

In theInternational Phonetic Alphabet the minuscule letter is used to represent avoiced velar fricative and the superscript modifier letter is used to representvelarization.^[6] It is not to be confused with the characterɤ, which looks like a lowercase Latin gamma that lies above thebaseline rather than crossing, and which represents theclose-mid back unrounded vowel. In certainnonstandard variations of the IPA, the uppercase form is used.^{[citation needed]}

It is as a full-fledged majuscule and minuscule letter in the alphabets of some oflanguages of Africa such asDagbani,Dinka,Kabye, andEwe,^[7] andBerber languages using theBerber Latin alphabet.

It is sometimes also used in the romanization ofPashto.

Mathematics and science

Lowercase

The lowercase letter $\gamma$ is used as a symbol for:

Chromatic number of ingraph theory
Gamma radiation innuclear physics
Shear strain in physics^[8]
Surface tension in physics^[9]
Thephoton, the elementary particle of light and otherelectromagnetic radiation
The 434 nmspectral line in theBalmer series^[10]
Surface energy inmaterials science
TheLorentz factor in thetheory of relativity^[11]
In mathematics, thelower incomplete gamma function^[12]
Theheat capacity ratioC_p /C_v inthermodynamics
Theactivity coefficient inthermodynamics
Thegyromagnetic ratio inelectromagnetism
Gamma waves inneuroscience
Gamma motor neurons inneuroscience
A non-SI metric unit of measure ofmass equal to onemicrogram (1 μg).^[13]^[14] This always-rare use is deprecated.
A non-SI unit of measure ofmagnetic flux density, sometimes used ingeophysics, equal to 10⁻⁵gauss (G), or 1nano tesla (nT).^[15]
The power by which the luminance of an image is increased ingamma correction
In civil and mechanical engineering:
- Specific weight
- Theshear rate of a fluid is represented by a lowercase gamma with a dot above it: ${\dot {\gamma }}$
- Austenite (also known as γ-iron), a metallic non-magnetic allotrope or solid solution of iron.
The gamma carbon, the third carbon attached to afunctional group inorganic chemistry andbiochemistry; seeAlpha and beta carbon
Hermite constant^[16]
TheEuler’s Constant also known as Euler–Mascheroni constant ≈ 0.57721566490153286^[17]^[18]
Stieltjes constants^[19]
Chvátal–Sankoff constants

The lowercase Latin gamma ɣ can also be used in contexts (such as chemical or molecule nomenclature) where gamma must not be confused with the lettery, which can occur in some computer typefaces.

Uppercase

The uppercase letter $\Gamma$ is used as a symbol for:

In mathematics, thegamma function (usually written as $\Gamma$ -function) is an extension of thefactorial tocomplex numbers^[20]^[21]
In mathematics, theupper incomplete gamma function^[22]
TheChristoffel symbols in differential geometry^[23]^[24]
In probability theory and statistics, thegamma distribution is a two-parameter family of continuous probability distributions.^[25]
Insolid-state physics, the center of theBrillouin zone
Circulation influid mechanics
Asreflection coefficient in physics and electrical engineering^[26]
The tape alphabet of aTuring machine^[27]
TheFeferman–Schütte ordinal $\Gamma _{0}$ ^[28]
Congruence subgroups of the modular group of other arithmetic groups
One of theGreeks in mathematical finance

Music

InMedieval music theory, Gamma was the starting note of the musical scale using theGuidonian hand. Paired with theSolfège syllableut, it became the origin for the word "gamut" ("Gammaut").^[29]

Unicode

U+0194 ƔLATIN CAPITAL LETTER GAMMA
U+0263 ɣLATIN SMALL LETTER GAMMA
U+0264 ɤLATIN SMALL LETTER RAMS HORN
U+02E0 ˠMODIFIER LETTER SMALL GAMMA
U+0393 ΓGREEK CAPITAL LETTER GAMMA (Γ)
U+03B3 γGREEK SMALL LETTER GAMMA (γ)
U+1D26 ᴦGREEK LETTER SMALL CAPITAL GAMMA
U+1D5E ᵞMODIFIER LETTER SMALL GREEK GAMMA
U+1D67 ᵧGREEK SUBSCRIPT SMALL LETTER GAMMA
U+213D ℽDOUBLE-STRUCK SMALL GAMMA
U+213E ℾDOUBLE-STRUCK CAPITAL GAMMA
U+2C84 ⲄCOPTIC CAPITAL LETTER GAMMA
U+2C85 ⲅCOPTIC SMALL LETTER GAMMA
U+1D6AA 𝚪MATHEMATICAL BOLD CAPITAL GAMMA^[a]
U+1D6C4 𝛄MATHEMATICAL BOLD SMALL GAMMA
U+1D6E4 𝛤MATHEMATICAL ITALIC CAPITAL GAMMA
U+1D6FE 𝛾MATHEMATICAL ITALIC SMALL GAMMA
U+1D71E 𝜞MATHEMATICAL BOLD ITALIC CAPITAL GAMMA
U+1D738 𝜸MATHEMATICAL BOLD ITALIC SMALL GAMMA
U+1D758 𝝘MATHEMATICAL SANS-SERIF BOLD CAPITAL GAMMA
U+1D772 𝝲MATHEMATICAL SANS-SERIF BOLD SMALL GAMMA
U+1D792 𝞒MATHEMATICAL SANS-SERIF BOLD ITALIC CAPITAL GAMMA
U+1D7AC 𝞬MATHEMATICAL SANS-SERIF BOLD ITALIC SMALL GAMMA

^TheMATHEMATICAL symbols should only be used in mathematics. Stylized Greek text should be encoded using the normal Greek letters, with markup and formatting to indicate text style.

See also

Look upΓ orγ in Wiktionary, the free dictionary.

Look upƔ orɣ in Wiktionary, the free dictionary.

References

^"gamma".Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription orparticipating institution membership required.)
^Russell, Bertrand (1972).A history of western philosophy (60th print. ed.). New York: Touchstone book.ISBN 9780671314002.
^Powell, Barry B. (2012).Writing: Theory and History of the Technology of Civilization. John Wiley & Sons. p. 182.ISBN 978-1-118-29349-2.
^Hamilton, Gordon James (2006).The Origins of the West Semitic Alphabet in Egyptian Scripts. Catholic Biblical Association of America. pp. 53–6.ISBN 978-0-915170-40-1.
^"Greek Alphabet Symbols". Rapid Tables. Retrieved25 August 2014.
^"IPA symbols with Unicode decimal and hex codes".www.internationalphoneticalphabet.org. Retrieved2025-09-24.ɣ ... vd velar fricative
^Practical Orthography of African Languages
^Elert, Glenn (2023),"Special Symbols",The Physics Hypertextbook, hypertextbook, retrieved2025-02-01,γ shear strain
^Elert, Glenn (2023),"Special Symbols",The Physics Hypertextbook, hypertextbook, retrieved2025-02-01,γ surface tension
^"1.4: The Hydrogen Atomic Spectrum".Chemistry LibreTexts. 2014-06-17. Retrieved2025-01-23.
^Fayngold, Moses (2008).Special relativity and how it works. Physics textbook. Weinheim: Wiley-VCH. p. 32.ISBN 978-3-527-40607-4.Because we will come across this coefficient quite often, we will give it a special name, the Lorentz factor, and stick to our symbol γ(V),...
^Weisstein, Eric W."Incomplete Gamma Function".mathworld.wolfram.com. Retrieved2025-01-23.
^François Cardarelli (2003).Encyclopaedia of Scientific Units, Weights and Measures. London: Springer-Verlag.ISBN 978-1-4471-1122-1.
^Betty Grover Eisner, Ph.D. (August 7, 2002).Remembrances of LSD therapy past(PDF). p. 14.Archived(PDF) from the original on 2014-12-05.that fateful 100 gamma, the same dosage I had had at my first LSD session
^Weisstein, Eric W. (30 April 2023)."Gamma -- from Eric Weisstein's World of Physics".scienceworld.wolfram.com.
^Weisstein, Eric W."Hermite Constants".mathworld.wolfram.com. Retrieved2025-01-31.
^Weisstein, Eric W."Euler-Mascheroni Constant".mathworld.wolfram.com. Retrieved2025-01-23.
^"DLMF: §5.2 Definitions ‣ Properties ‣ Chapter 5 Gamma Function".dlmf.nist.gov. Retrieved2025-01-31.
^Weisstein, Eric W."Stieltjes Constants".mathworld.wolfram.com. Retrieved2025-01-31.
^Weisstein, Eric W."Gamma Function".mathworld.wolfram.com. Retrieved2025-01-22.The (complete) gamma function Γ(n) is defined to be an extension of the factorial to complex and real number arguments.
^"DLMF: §5.1 Special Notation ‣ Notation ‣ Chapter 5 Gamma Function".dlmf.nist.gov. Retrieved2025-01-31.
^Weisstein, Eric W."Incomplete Gamma Function".mathworld.wolfram.com. Retrieved2025-01-22.
^Baumann, Gerd (2005).Mathematica for theoretical physics (2nd ed.). New York: Springer. p. 731.ISBN 978-0-387-01674-0.
^Weisstein, Eric W."Christoffel Symbol of the First Kind".mathworld.wolfram.com. Retrieved2025-01-22.
^Weisstein, Eric W."Gamma Distribution".mathworld.wolfram.com. Retrieved2025-01-22.
^Zhang, Keqian; Li, Dejie, eds. (2008).Electromagnetic Theory for Microwaves and Optoelectronics. SpringerLink Bücher (2nd ed.). Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg. p. 82.ISBN 978-3-540-74295-1.The reflection coefficient Γis real when medium 1 and medium 2 are both lossless media,…
^Arora, Sanjeev; Barak, Boaz (2016).Computational complexity: A Modern Approach (4th printing 2016 ed.). New York: Cambridge University Press. p. 12.ISBN 978-0-521-42426-4.A tape is an infinite one-directional line of cells, each of which can hold a symbol from a finite set Γcalled the alphabet of the machine.
^Kahle, Reinhard; Rathjen, Michael (2020).The legacy of Kurt Schütte. Cham: Springer. p. 41.ISBN 978-3-030-49423-0.The Veblen approach was quite sufficient even for the ordinal, now known as the Feferman–Schütte ordinal, Γ₀ for predictive analysis
^Merriam Webster.Gamut.https://www.merriam-webster.com/dictionary/gamut

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