who's who

noun, often capitalized both Ws
\ ˌhüz-ˈhü \

Definition of who's who

 (Entry 1 of 5)

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

everybody who's anybody

idiom (1)

Definition of everybody who's anybody (Entry 2 of 5)

: every important or well-known person Everybody who's anybody was there.

everyone who's anyone

idiom (2)

Definition of everyone who's anyone (Entry 3 of 5)

: every important or well-known person Everyone who's anyone will be there.

show (someone) who's boss

idiom (3)

Definition of show (someone) who's boss (Entry 4 of 5)

: to do something that will cause (someone) to recognize one's authority He thinks he can tell me what to do, but I'll show him who's boss.

who's counting?

idiom (4)

Definition of who's counting? (Entry 5 of 5)

informal + humorous
used to say that one does not care about how large a number is Tomorrow's my 84th birthday, but who's counting?

First Known Use of who's who


1917, in the meaning defined at sense 1

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who's counting?

who's who


who asked you?

who can tell

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

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esteemed in general opinion

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