Mega

Mega

Prefix / Adjective (informal) · /ˈmɛɡ.ə/

Definition

(Prefix) denoting a factor of one million in the metric system (megawatt, megabyte in some conventions); denoting very large size or scale (megacity, megastructure); (Adjective, informal, British) very large, excellent, or impressive.

Origin

From Greek megas (great, large), from Proto-Indo-European *meg- (great). The same root gives magnitude, magnificent, magnify, major, and the prefix magni-. As an SI prefix, mega- represents 10⁶ (one million) and was formally adopted in 1960. In British informal speech, mega developed as a freestanding adjective meaning very good or very large from around the 1980s.