gamma

n. third letter of the Greek alphabet

Gamma (uppercase Γ, lowercase γ) is the third letter of the Greek alphabet. In the system of Greek numerals it has a value of 3. It was derived from the Phoenician letter Gimel . Letters that arose from Gamma include the Roman C and G and the Cyrillic letters Ge Г and Ghe Ґ. In Modern Greek, it represents either a voiced velar fricative  or a voiced palatal fricative . In Ancient Greek, it represented a voiced velar stop . Before velars, it represents a velar nasal  in Modern as well as Ancient Greek, and a double gamma represents a prenasalized voiced velar stop .
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Gamma /gam·ma/ 1. third letter of the Greek alphabet, see also ?-. 2. obsolete equivalent for microgram. gam·ma n. 1. [more]Gamma - Community and Resources

Noun
1. 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)
(synonym) da Gamma, Vasco da Gamma
(hypernym) navigator

Noun
1. the 3rd letter of the Greek alphabet
(hypernym) letter, letter of the alphabet, alphabetic character
(member-holonym) Greek alphabet
2. a unit of magnetic field strength equal to one-hundred-thousandth of an oersted
(hypernym) field strength unit
(part-holonym) oersted

n. gamma, third letter of the Greek alphabet