who's who

American  

noun

1. a reference work containing short biographical entries on the outstanding persons in a country, industry, profession, etc..

   a who's who in automotive engineering.

2. the outstanding or influential persons in a community, industry, profession, or other group.

   The who's who of racing will be there.

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who's who British  

noun

1. a book or list containing the names and short biographies of famous people

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who's who Idioms  

1. The outstanding or best-known individuals of a group, as in Tonight's concert features a veritable who's who of musicians. This expression comes from the name of a famous reference work, Who's Who, first published in 1849, which contains biographical sketches of famous individuals and is regularly updated. Its name in turn was based on who is who, that is, the identity of each of a number of persons, a phrase dating from the late 1300s. [Early 1900s]

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Etymology

Origin of who's who

First recorded in 1840–50

Example Sentences

His first order of business was to invite a veritable who’s who of local arts groups and events to call the venue home.

From Los Angeles Times

And he brought together a who’s who of business leaders, politicians and generals to advise the bank on the “Security and Resiliency Initiative.”

From The Wall Street Journal

The feasts began in 1997 and have continued apace every other year since then, featuring a who’s who of literary accomplishment across every genre.

From Los Angeles Times

“If you have someone who’s who doesn’t feel stable in their job, they’re probably not going to go through with the home purchase.”

From Barron's

Smithson’s biographer, Heather Ewing, has noted that Smithson was friends with a “who’s who of European science,” men who “proclaimed themselves citizens of the globe.”

From The Wall Street Journal