Also found in: Dictionary, Thesaurus, Medical, Legal, Financial, Acronyms, Idioms, Wikipedia.
mega(1) Million (10 to the 6th power). Abbreviated "M," it is a prefix for capacities and speeds (megabits, megabytes, megahertz, etc.). Mega may refer to 1,000,000 or 1,048,576, the latter based on the binary system (see NIST binary). See MB, meg, binary values and space/time.
(2) A prefix attached to common, non-computer words that means a very large size or quantity. For example, "megabucks" means a lot of money. Both "mega" and "giga" are used in this manner, although mega means million and giga means billion. See giga.
(3) (MEGA) A brand name for various models of Atari's ST and STE personal computers. See ST and Atari.