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megabuck

[meg-uh-buhk]
noun Informal.
  1. one million dollars.
  2. megabucks, very large sums of money.

Origin of megabuck

First recorded in 1945–50; mega- + buck1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for megabucks

megabuck

noun
  1. US and Canadian slang
    1. a million dollars
    2. (as modifier)a megabuck movie
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 megabucks
n.

1946, originally "one million dollars," from mega- in the scientific sense + slang buck (n.) "dollar." A jocular coinage of U.S. scientists working on expensive atomic research.

Online Etymology Dictionary, © 2010 Douglas Harper