done deal, a

a done deal

Something that has been decided or finalized. Once we sign those papers, the sale of the house will be a done deal. I had no idea I'd have to make more payments to receive the merchandise—I thought it was a done deal!
See also: deal, done
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

done deal

An irrevocable agreement, as in Once you've signed the lease, it's a done deal. This slangy expression, first recorded in 1979, may have come from done thing, originating in the late 1600s.
See also: deal, done
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.

a done deal

If something such as a plan or project is a done deal, it has been completed or arranged and it cannot be changed. He called a journalist to announce that his nomination was a done deal. The pact is far from being a done deal. It must be ratified by the legislative bodies of all three countries.
See also: deal, done
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012

a done deal

a plan or project that has been finalized or accomplished.
1991 New Yorker The French are still overreacting to German unification, even though it is a done deal.
See also: deal, done
Farlex Partner Idioms Dictionary © Farlex 2017

a done ˈdeal

(especially American English) used to describe a decision, an arrangement, a project, etc. that is completed and cannot be changed: The managing director denied that the merger was a done deal, and said they were still in negotiations.
See also: deal, done
Farlex Partner Idioms Dictionary © Farlex 2017

done deal

n. a completed deal; something that is settled. The sale of the property is a done deal. There is nothing that can be changed now.
See also: deal, done
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

done deal, a

An irreversible agreement, a final decision or compact. This relatively new synonym for the long-used fait accompli dates only from the late 1970s, but according to William Safire, it had a near predecessor in a done thing. The latter surfaced about 1700, and Dickens used it: “It was a done thing between him and Scrooge’s nephew” (A Christmas Carol, 1843). The current cliché is also often used in the negative (not a done deal), as in “We can interview another architect; it’s not a done deal, you know.”
See also: done
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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