Is it ensure, insure, or assure?
late 14c., "self-restraint," from Old French continence (14c.), from Latin continentia "a holding back, repression," from continent-, present participle stem of continere (see continent). Especially of sexual desire from late 14c.; of the body's eliminatory functions, from 1915. Related: Continency.
continence con·ti·nence (kŏn'tə-nəns)
Voluntary control over urinary and fecal discharge.
Partial or complete abstention from sexual activity.