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gamma
gam·ma G0031800 (găm′ə)n.1. The third letter of the Greek alphabet. See Table at 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.adj. Chemistry 1. Being in the third position relative to a designated carbon atom in an organic molecule at which an atom or a group may be substituted.2. Referring to the third of a group of isomers, or molecules of similar origin or properties, determined arbitrarily by those who discover or classify them. Used in combination.
[Middle English, from Greek, of Phoenician origin; see gml in Semitic roots.]gamma (ˈɡæmə) n1. (Letters of the Alphabet (Foreign)) the third letter in the Greek alphabet (Γ, γ), a consonant, transliterated as g. When double, it is transcribed and pronounced as ng2. (Education) the third highest grade or mark, as in an examination3. (Units) a unit of magnetic field strength equal to 10–5 oersted. 1 gamma is equivalent to 0.795 775 × 10–3 ampere per metre4. (Photography) photog television the numerical value of the slope of the characteristic curve of a photographic emulsion or television camera; a measure of the contrast reproduced in a photographic or television image5. (Electronics) photog television the numerical value of the slope of the characteristic curve of a photographic emulsion or television camera; a measure of the contrast reproduced in a photographic or television image6. (Atomic Physics) involving or relating to photons of very high energy: a gamma detector. 7. (Chemistry) relating to one of two or more allotropes or crystal structures of a solid: gamma iron. 8. (Chemistry) relating to one of two or more isomeric forms of a chemical compound, esp one in which a group is attached to the carbon atom next but one to the atom to which the principal group is attached[C14: from Greek; related to Hebrew gīmel third letter of the Hebrew alphabet (probably: camel)]
Gamma (ˈɡæmə) n (Astronomy) (foll by the genitive case of a specified constellation) the third brightest star in a constellation: Gamma Leonis. gam•ma (ˈgæm ə)
n., pl. -mas. 1. the third letter of the Greek alphabet (Ɣ, γ). 2. the third in a series of items. 3. (cap.) a star that is usu. the third brightest of a constellation. 4. a unit of weight equal to one microgram. 5. a unit of magnetic field strength, equal to 10−5 gauss. 6. a measure of the degree of development of a photographic negative or print. [< Greek gámma] Thesaurus| Noun | 1. |  gamma - the 3rd letter of the Greek alphabetGreek alphabet - the alphabet used by ancient Greeksalphabetic character, letter of the alphabet, letter - the conventional characters of the alphabet used to represent speech; "his grandmother taught him his letters" | | 2. | gamma - a unit of magnetic field strength equal to one-hundred-thousandth of an oerstedfield strength unit - an electromagnetic unit of magnetic intensityoersted - the magnetic field strength 1 cm from a unit magnetic pole | | 3. |  Gamma - Portuguese navigator who led an expedition around the Cape of Good Hope in 1497; he sighted and named Natal on Christmas Day before crossing the Indian Ocean (1469-1524)da Gamma, Vasco da Gamma |
Translationsgamma (ˈgӕmə) : gamma rays a powerful form of radiation. 伽瑪射線 伽马gamma
gamma1. the third letter in the Greek alphabet (Γ, γ), a consonant, transliterated as g. When double, it is transcribed and pronounced as ng 2. the third highest grade or mark, as in an examination 3. a unit of magnetic field strength equal to 10--5 oersted. 1 gamma is equivalent to 0.795 775 × 10--3 ampere per metre 4. Photog Television the numerical value of the slope of the characteristic curve of a photographic emulsion or television camera; a measure of the contrast reproduced in a photographic or television image 5. a. involving or relating to photons of very high energy b. relating to one of two or more allotropes or crystal structures of a solid c. relating to one of two or more isomeric forms of a chemical compound, esp one in which a group is attached to the carbon atom next but one to the atom to which the principal group is attached gamma (gam -ă) (γ) The third letter of the Greek alphabet, used in stellar nomenclature usually to designate the third-brightest star in a constellation or sometimes to indicate a star's position in a group.Gamma (1) A conventional unit that is sometimes used for measurements of small masses: 1 gamma = 10-6 g. The designation “microgram” (μg) is more frequently used than “gamma.” (2) The name of a hundred-thousandth part of an oersted (the unit of magnetic field strength in the cgs system of units) that is used mainly for measurements of terrestrial magnetism and cosmic magnetic fields. It is designated by y.
Gamma the quantitative characteristic of the ability of photographic material to transmit the difference in exposure H of various parts of a photographic image by the difference in the optical density D of the parts. The gamma is equal to the tangent of the angle of inclination to the axis log H of the straight portion of the performance curve of the material (provided that the scales of the axes log H and D are identical). Other conditions being equal, the gamma characterizes the uniformity of the silver halide crystals of the photographic emulsion with respect to light sensitivity. As a rule, it is greater for low-sensitivity positive materials and less for high-sensitivity negative materials. The gamma is one of the most important sensitometric parameters of a photographic material. gamma[′gam·ə] (chemistry) The gamma position (the third carbon atom in an aliphatic carbon chain) on a chemical compound. (electromagnetism) A unit of magnetic field strength, equal to 10 microoersteds, or 0.00001 oersted. (graphic arts) A numerical indication of the degree of contrast in a television or photographic image; equal to the slope of the straight-line portion of the H and D curve for the emulsion or screen. (mechanics) A unit of mass equal to 10-6 gram or 10-9 kilogram. GAMMA (language)1. A language for matrices and generation ofmathematical programming reports.
["GAMMA 3.3 for MPS/MPSX, IBM System:/360", Bonnor & MooreAssocs (Mar 1975)].
2. A high-level parallel language.
[Research Directions in High-Level Parallel Languages,LeMetayer ed, Springer 1992].gammaGamma is a number that represents the relationship between digital pixels and luminance, which is inherently nonlinear. For years, there has been a misconception that gamma had to be corrected due to the inherent deficiency in earlier CRT monitors. In fact, the CRT generated almost the inverse of a human's perception of luminance and thus actually evened out this relationship.
Gamma Correction
A gamma correction number is applied to ensure that the digital pixels produce a uniform luminance across the entire tonal realm from dark to bright, especially in the midtones. Because LCD monitors were designed to emulate the CRT's gamma, gamma correction is still used. With gamma correction, eight bits per pixel is sufficient; otherwise, 11 bits per pixel would be required. See color depth and pixel.gamma
γ gamma, the third letter of the Greek alphabet, often used to indicate the third member of a series, such as the γ chain of hemoglobin. See also terms beginning gamma.
gamma [gam´ah] the third letter of the Greek alphabet, γ, used in names of chemical compounds to distinguish one of three or more isomers or to indicate the position of substituting atoms or groups.gamma chain disease a type of heavy chain disease that resembles a malignant lymphoma, with symptoms of lymphadenopathy, hepatosplenomegaly, and recurrent infections.gamma globulin 1. a class of plasma proteins composed almost entirely of immunoglobulins, the proteins that function as antibodies. Production of gamma globulin may be increased in the body when there is invasion by harmful microorganisms. An abnormal amount in the blood, a condition known as hypergammaglobulinemia" >hypergammaglobulinemia, may be indicative of a chronic infection or certain malignant blood diseases. There is also a rare condition, agammaglobulinemia, in which the body is unable to produce gamma globulin; patients suffering from this are extremely susceptible to infection and must be given frequent injections of gamma globulin serum.2. immune globulin.gamma rays (γ-rays) electromagnetic emissions from radioactive substances; they are similar to and have the same general properties as x-rays but are produced through the disintegration of certain radioactive elements. They consist of high energy photons, have short wavelengths, and have no mass and no electric charge. Gamma rays are sometimes used in the treatment of deep-seated malignancies (see radiation therapy).γ1. Third letter in the Greek alphabet, gamma. 2. In chemistry, denotes the third in a series, the fourth carbon in an aliphatic acid, or position 2 removed from the α position in the benzene ring. 3. Symbol for 10-4 gauss; surface tension; activity coefficient; microgram. 4. Symbol for photon. For terms having this prefix, see the specific term.
gam·ma (gam'ă), 1. Third letter of the Greek alphabet, γ. 2. A unit of magnetic field intensity equal to 10-9 T. [G.] gamma (1) Microgram; 10-6g.
(2) An obsolete, non-SI (International System) unit of magnetic field strength equal to 0.795/0.775 ampere/m.gamma γ Symbol for: 1. Heavy chain of immunoglobulin G–IgG.2. Hemoglobin monomeric chain.3. Photon.4. The 3rd carbon in an aliphatic organic molecule Genetics A value calculated by the ratio between synonymous DNA mutations, which don't result in a different amino acid being translated from a codon, and nonsynonymous mutations–which result in a different amino acid being encoded Imaging A measure of contrast 1. Film–The slope of the density vs. exposure curve 2. Electronic display terminology–The slope of the brightness distribution curve; a large gamma indicates a steep slope and high contrast.γ Abbreviation for activity coefficient;gamma;photon.
γ 1. Gamma (q.v.). 2. Abbreviation for activity coefficient; surface tension.
gam·ma (γ) (gam'ă) 1. Third letter in the Greek alphabet. 2. chemistry The third in a series, the fourth carbon in an aliphatic acid, or position 2 removed from the α position in the benzene ring. 3. Symbol for 10-4 gauss. 4. For terms with the prefix γ, see the specific term. [G.]gamma The third letter of the Greek alphabet. Often used in medicine to denote a particular class.gamma (y) radiation electromagnetic radiation of shorter wavelength and higher energy than X-RAYS. See ELECTROMAGNETIC SPECTRUM.γ Third letter in the Greek alphabet, gamma; photon. Gamma
GammaThe ratio of a change in the option delta to a small change in the price of the asset on which the option is written.GammaA measure of how fast the delta changes. That is, gamma is a mathematical measurement of how fast the price of an option contract changes for each unit of change in the price of the underlying asset. The larger the gamma, the more volatile the option contract is. If an option is at the money or near the money, gamma is large, but if it is deep in or deep out of the money, gamma can become quite small. This is because when an option is near the money, a small change in the underlying asset's value can greatly change the level of demand for the contract. This is not the case for deep in and deep out of the money options.gamma The sensitivity of an option's delta to changes in the price of the underlying asset. The gamma of an option is greatest when an option is near the money (strike price close to market price of underlying asset) and near zero when an option is deep out of the money.GAMMA
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| GAMMA➣Greeks Advocating Mature Management of Alcohol | | GAMMA➣Genoa Active Message MAchine | | GAMMA➣Geometric Algorithms for Modeling, Motion and Animation | | GAMMA➣General Approach to Magnetic resonance Mathematical Analysis | | GAMMA➣Génération Automatique de Maillages et Méthodes d'Adaptation | | GAMMA➣Groupement Automobile Monégasque de Mécanique Avancée | | GAMMA➣Gay and Married Men Association | | GAMMA➣Guide Star Astrometric Measuring Machine | | GAMMA➣Georgia Model Missile Association | | GAMMA➣Guinea, Angola, Mozambique Medical Action | | GAMMA➣Graphic Art and Multimedia Artists |
gamma
Related to gamma: gamma radiation, Gamma rays, Gamma function, gamma globulin, Gamma distribution, praxisWords related to gammanoun the 3rd letter of the Greek alphabetRelated Words- Greek alphabet
- alphabetic character
- letter of the alphabet
- letter
noun a unit of magnetic field strength equal to one-hundred-thousandth of an oerstedRelated Words- field strength unit
- oersted
noun Portuguese navigator who led an expedition around the Cape of Good Hope in 1497Synonyms |