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

The tracklist, revealed yesterday, is like a who's who of indie rock.

From BBC

One of the top designers of his era -- best known as just Valentino -- his creations were worn by the who's who of the international elite, from Elizabeth Taylor and Nancy Reagan through to Sharon Stone, Julia Roberts and Gwyneth Paltrow.

From Barron's

A who’s who of high finance caught foreclosure fever, dispatching buyers to courthouse steps with duffel bags of cashiers checks to buy repossessed homes.

From The Wall Street Journal

A who's who of cricket greats have posted messages of support, including former England skipper Michael Vaughan and Indian legends Ravichandran Ashwin and VVS Laxman.

From Barron's

Bez from the Happy Mondays was also in attendance at the funeral, which was a veritable Who's Who of legendary music figures from the city.

From BBC