megohm; megohms.




a megabyte.




a female given name, form of Margaret.



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 of mega-

combining form representing Greek mégas large, great Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for meg

romp, meg, gamine, spitfire, hoyden, hoiden

Examples from the Web for meg

Contemporary Examples of meg

Historical Examples of meg

  • I went to Meg Van Dam, who had long urged me to pay her a visit.

  • Meg paced the floor a minute, then slapped herself into a chair.

  • I dashed into my room but Meg's staccato reached me even there.

  • Perhaps I shouldn't have let her talk so about Meg, but, after all, she told me nothing new.

  • Meg, at sixteen, had received so little from life that her expectations were of the humblest.

    Jan and Her Job

    L. Allen Harker

British Dictionary definitions for meg



informal short for megabyte


combining form

denoting 10 6megawatt Symbol: M
(in computer technology) denoting 2 20 (1 048 576)megabyte
large or greatmegalith
informal great in importance or amountmegastar

Word Origin for mega-

from Greek megas huge, powerful
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for meg


fem. proper name; before the late 20c. rise in popularity of Megan it typically was a pet form of Margaret, and was "used dial. to indicate a hoyden, coarse woman, etc." [OED]


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]
Online Etymology Dictionary, © 2010 Douglas Harper

meg in Medicine



One million (106):megahertz.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

meg in Science


A prefix that means:
Large, as in megadose, a large dose.
One million, as in megahertz, one million hertz.
220 (that is, 1,048,576), which is the power of 2 closest to a million, as in megabyte.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.