an important or impressive person or thing: to make a big deal out of nothing; I hear he's a big deal on Wall Street now.
(used ironically as an interjection to indicate that one considers something to be unimportant or unimpressive): So you're the mayor's cousin—big deal!
Origin of big deal
First recorded in 1945–50
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for big deal
slang an exclamation of scorn, derision, etc, used esp to belittle a claim or offer
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 big deal
from mid-19c. in poker or business; as an ironic expression, popular in American English from c.1965, perhaps a translated Yiddishism (cf. a groyser kunst).
Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with big deal
A matter of great interest or importance, as in Performing in Symphony Hall is a big deal for everyone in the chorus. [c. 1940] Also see under make a federal case out of.
So what? Who cares? For example, So you got the job after all—well, big deal! This use of the phrase as an ironic interjection dates from approximately the same time.
The American Heritage® Idioms Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.