gamma

(găm'ə)
n.

1. The third letter of the Greek alphabet.
2. The third item in a series or system of classification.
3. A unit of magnetic intensity equal to one hundred thousandth (10 ^-5) of an oersted.
4. A unit of mass equal to one millionth (10 ^-6) of a gram.
5. Chemistry. The third position from a designated carbon atom in an organic molecule at which an atom or a radical may be substituted.

[Middle English, from Greek, of Phoenician origin.]

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Variant: γ

A measure of association, of the type known as proportional reduction in error, suitable for examining the association between two ordinal variables.

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[Etymology: Anglicized name of the Greek letter ‘g’] mass. Symbol γ. A one- time popular, but now obsolete and SI-deprecated name for the microgram (μg).

mechanics (more usually G) See Newtonian constant of gravitation.

electromagnetics Metric-c.g.s.-Gaussian A very small unit of magnetic flux density, appropriate for describing variations in the intensity of Earth's magnetic field,
[Chree C. Nature Vol. 69, 6 (1903)] but obsolete; 10^-5gauss, = 1 nT.

optics, electronics A measure of amplification, usually the ratio of the logarithms of output and input, akin to the decibel.

photography For contrast enhancement, as above for optics. Also a measure of development of an emulsion, dependent on the developer and increasing with time to a limiting value termed ‘gamma infinity’. Hence the slope of a response curve for an electronic photomultiplier, relating, for instance, brightness to excitation, e.g. for specifying CRTs.

The way brightness is distributed across the intensity spectrum by a monitor, printer or scanner. Depending on the device, the gamma may have a significant effect on the way colors are perceived. Gamma is technically the relationship between the input voltage and resulting intensity of the output. A perfect linear device would have a gamma of 1.0 and be plotted on a graph called a "tone curve" as a straight line. Although a scanner is fairly linear, the tone curve of a monitor or printer is bent, yielding a gamma in the range of 1.8 to 2.6, which effects midrange tones. See gamma correction.

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Trigonometric unit of measure of the degree of contrast between the darkest and lightest areas in a photographic image. See also high contrast.

The rate of change for delta with respect to the underlying asset's price.

Investopedia Says:
Mathematically, gamma is the first derivative of delta and is used when trying to gauge the price of an option relative to the amount it is in or out of the money.

When the option being measured is deep in or out of the money, gamma is small. When the option is near the money, gamma is largest.

Related Links:
Find the middle ground between conservative and high-risk options strategies. Gamma-Delta Neutral Option Spreads
Learn why option spreads offer trading opportunities with limited risk and greater versatility. Option Spread Strategies
These risk-exposure measurements help traders detect how sensitive a specific trade is to price, volatility and time decay. Using "The Greeks" To Understand Options
Learn about this hedge ratio, which tells us how many contracts are needed to hedge a position in the underlying. Going Beyond Simple Delta: Understanding Position Delta
Understanding price influences on options positions requires learning delta, theta, vega and gamma. Getting To Know The "Greeks"

symbol: γ (lower case) or Γ (upper case); the third letter of the Greek alphabet. For uses see Greek alphabet.

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Dansk (Danish)
n. - mikrogram

Nederlands (Dutch)
gamma, derde in een serie

Français (French)
n. - gamma

Deutsch (German)
n. - Gamma, die Note drei, das Dritte

Ελληνική (Greek)
n. - (το ελληνικό γράμμα) γάμμα
attrib. - γάμμα

Italiano (Italian)
gamma

Português (Portuguese)
n. - gama (m), terceiro (m) de uma série

Русский (Russian)
гамма (третья буква греческого алфавита), третий по величине или значимости, посредственная оценка

Español (Spanish)
n. - gamma, gama, el tercero en una serie de cosas, unidad de peso igual a un microgramo, unidad de fuerza de campo magnético

Svenska (Swedish)
n. - gamma (grekiska bokstaven)
attr. - gamma-

中文（简体）(Chinese (Simplified))
希腊字母的第三个, 伽马

中文（繁體）(Chinese (Traditional))
n. - 希臘字母的第三個, 伽馬

한국어 (Korean)
n. - 감마(그리스 글자 중 세 번째의 글자), 제 3의 것

日本語 (Japanese)
n. - ガンマ

العربيه (Arabic)
‏(الاسم) غاما, الجيم (صفه) جيمي‏

עברית (Hebrew)
n. - ‮גמה (אות יוונית)‬

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