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crack a smile

Idioms  

  1. Smile, as in Betty was a very serious person; she rarely cracked a smile. This colloquialism transfers crack in the sense of “break” to breaking a serious facial expression into a smile.

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.