Is it ensure, insure, or assure?
mid-14c., shortening of chicken (n.), extended to human offspring (often in alliterative pairing chick and child) and thence 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 in this sense 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.