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mega-

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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

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Also especially before a vowel, meg-.

Origin of mega-

Combining form representing Greek mégas large, great
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

Example sentences from the Web for mega-

British Dictionary definitions for mega- (1 of 2)

mega
/ (ˈmɛɡə) /

adjective

slang extremely good, great, or successful

Word Origin for mega

C20: probably independent use of mega-

British Dictionary definitions for mega- (2 of 2)

mega-

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

Medical definitions for mega-

mega-

pref.

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

Scientific definitions for mega-

mega-

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.
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