/gam"euh/ , n.
1. the third letter of the Greek alphabet.
2. the consonant sound represented by this letter.
3. the third in a series of items.
4. ( cap. ) Astron. a star that is usually the third brightest of a constellation: The third brightest star in the Southern Cross is Gamma Crucis.
5. a unit of weight equal to one microgram.
6. Physics. a unit of magnetic field strength, equal to 10 -5 gauss.
7. Photog. a measure of the degree of development of a negative or print.
8. Television. an analogous numerical indication of the degree of contrast between light and dark in the reproduction of an image in television.
9. Chiefly Brit. a grade showing that an individual student is in the third, or lowest, of three scholastic sections in a class. Cf. alpha (def. 7), beta (def. 8).
[ gámma ]