who's who

noun, often capitalized both Ws
\ ˌhüz-ˈhü How to pronounce who's who (audio) \

Definition of who's who

1 : a compilation of brief biographical sketches of prominent persons in a particular field a who's who of sports figures
2 : the leaders of a group : elite
3 : a listing or grouping of notable persons or things

First Known Use of who's who

1917, in the meaning defined at sense 1

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

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Cite this Entry

“Who's who.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/who%27s%20who. Accessed 7 Dec. 2021.

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