c.1320, abbreviation of chicken (q.v.), extended to human offspring (often in alliterative pairing chick and child) and used as a term of endearment. As slang for "young woman" it is first recorded 1927 (in "Elmer Gantry"), supposedly from U.S. black slang, in British use
by c.1940, popularized by Beatniks late 1950s. Chicken in this sense is from 1711. Sometimes c.1600-1900 chicken was taken as a plural, chick as a singular (cf. child/children) for the domestic fowl.