who's who


often capitalized both Ws
: a compilation of brief biographical sketches of prominent persons in a particular field
a who's who of sports figures
: the leaders of a group : elite
: a listing or grouping of notable persons or things

Word History

First Known Use

1917, in the meaning defined at sense 1

Time Traveler
The first known use of who's who was in 1917

Dictionary Entries Near who's who

Cite this Entry

“Who's who.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/who%27s%20who. Accessed 9 Feb. 2023.

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