I. ˈgamə noun
( -s )
Etymology: Middle English, from Late Latin, from Greek, of Semitic origin; akin to Hebrew gīmel gimel
1. : the third letter of the Greek alphabet — symbol Γ or γ; see alphabet table
2.
a. : the degree of contrast of a developed photographic image
b. : the slope of the straight-line portion of the characteristic curve of a photographic material or process
c. : a measure of the faithfulness with which the brightness variation in a television scene is reproduced in the displayed picture
3.
a. : a unit of magnetic intensity equal to 0.00001 oersted
b. : a gamma-ray quantum
c. : one millionth of a gram : microgram
II. adjective
or γ- “
1. : of or relating to one of three or more closely related chemical substances
γ-yohimbine
— used somewhat arbitrarily to specify ordinal relationship or to specify a particular physical form, especially an allotropic modification (as in γ-iron), or an isomeric or stereoisomeric form (as in γ-benzene hexachloride)
2. : third in position in the structure of an organic molecule from a particular group or atom or having a structure characterized by such a position
γ-hydroxy acids
γ-lactones
3. : third in order of brightness — used of a star in a constellation
4. of streptococci : producing no hemolysis on blood agar plates