big deal!

big deal

1. Something that is considered important or consequential. Being the first in her family to graduate college was a big deal to Katie. I'm kind of a big deal here, but I'll just be the new kid when I switch schools.
2. Who cares? That's not impressive or important. So you did 20 push-ups. Big deal, I can do 100. A: "Wow, a 1969 Mustang!" B: "Big deal. It's just a car."
See also: big, deal
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

big deal

1. 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.
2. 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.
See also: big, deal
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

big deal!

used to express contempt for something regarded as impressive or important by another person. informal
See also: big
Farlex Partner Idioms Dictionary © Farlex 2017

big ˈdeal

(informal, ironic) used for suggesting that something is not as important or impressive as somebody else thinks it is: ‘I’ve got tickets for next Saturday’s football match.’ ‘Big deal! Who’s interested in football anyway?’
See also: big, deal
Farlex Partner Idioms Dictionary © Farlex 2017

big deal

1. n. something really important. Don’t make such a big deal out of it!
2. exclam. So what!; What does it matter? (Usually Big deal!) So he snores! Big deal! Snore back!
See also: big, deal
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

big deal

An important matter; also, so what, who cares. The differentiation between these two phrases depends on the speaker’s tone. An example of the first sense might be, “A first helicopter ride for a five-year-old is a big deal.” The second sense appears in, “So she got her first choice of colleges—well, big deal!” This sense can also be conveyed by no big deal. All three usages date from about 1940.
See also: big, deal
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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References in periodicals archive ?
Of Course It's a Big Deal! A Story about Learning to React Calmly and Appropriately
"Of Course It's a Big Deal!" is a Boys Town Press title from a series of kid friendly books that help teach valuable social skills.
Everything is a big deal! But I love her for who she is inside, and that's why she's my BFF--despite the repeat performances over grades and boyfriend woes." Appreciate her need for attention and her humor.