mega-

1.
variant of megalo- (megalith); also the initial element in units of measure that are equal to one million of the units denoted by the base word (megahertz). Symbol: M.
Also, especially before a vowel, meg-.
Origin
combining form representing Greek mégas large, great
British Dictionary definitions for mega-

mega-

combining form
1.
denoting 106: megawatt, M
2.
(in computer technology) denoting 220 (1 048 576): megabyte
3.
large or great: megalith
4.
(informal) great in importance or amount: megastar
Word Origin
from Greek megas huge, powerful
Word Origin and History for mega-

before vowels meg-, word-forming element often meaning "large, great," but in precise scientific language "one million" (megaton, megawatt, etc.), from Greek megas "great, large, vast, big, high, tall; mighty, important" (fem. megale), from PIE *meg- "great" (cf. Latin magnus, Old English micel; see mickle). Mega began to be used alone as an adjective by 1982.

High-speed computer stores 2.5 megabits [headline in "Electronics" magazine, Oct. 1, 1957]

mega- in Medicine

mega- pref.

  1. Large: megacephaly.

  2. One million (106): megahertz.

mega- in Science
mega-  

  1. A prefix that means:

  2. Large, as in megadose, a large dose.

  3. One million, as in megahertz, one million hertz.

  4. 220 (that is, 1,048,576), which is the power of 2 closest to a million, as in megabyte.


mega- in Technology


prefix