piece of one's mind

a piece of (one's) mind

One's true thoughts or feelings about something, especially angry or frustrated criticism. Boy, the boss really gave me a piece of his mind during my performance review. This has to have been the worst service I've ever had a restaurant. I'm going to let the waiter have a piece of my mind!
See also: mind, of, piece
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

piece of one's mind

Frank and severe criticism, censure, as in Chuck was furious and gave him a piece of his mind. The word piece here is used in the sense of "portion," but the portion of the mind alluded to always has a negative opinion. [Second half of 1500s]
See also: mind, of, piece
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.

piece of one's mind, (to give someone) a

To express one’s disapproval quite plainly; to give one’s candid opinion. This term has been around since the sixteenth century. John Dryden used it in his play The Maiden Queen (1667, 2.1): “I have told her a piece of my mind already.”
See also: give, of, piece
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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