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Synonyms

know one's stuff

Idioms  

  1. Also, know one's onions. Be experienced or knowledgeable in one's field or in the matter at hand. For example, Patrice knows her stuff when it comes to Mexican history, or We need a handyman who knows his onions. The allusion in the variant is unclear. [First half of 1900s]

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.

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