A chorus line is a substantial group of dancers who together perform synchronized routines, usually in musical theatre. Sometimes, singing is also performed. Chorus line dancers in Broadway musicals and revues have been referred to by slang terms such as ponies, gypsies and twirlies. Ballet uses the term corps de ballet.

A Chorus Line is a musical with music by Marvin Hamlisch, lyrics by Edward Kleban and a book by James Kirkwood, Jr. and Nicholas Dante. Centred on seventeen Broadway dancers auditioning for spots on a chorus line, the musical is set on the bare stage of a Broadway theatre during an audition for a musical. A Chorus Line provides a glimpse into the personalities of the performers and the choreographer as they describe the events that have shaped their lives and their decisions to become dancers.