late 14c., "inability to restrain sexual desire, sexual immorality," later "inability to keep to a religious rule" (early 15c.), from Old French incontinence "lack of abstinence, unchastity" (12c.) or directly from Latin incontinentia "greediness; incontinence," noun of quality from incontinens "incontinent, immoderate, intemperate" (see incontinent). Meaning "inability to retain bodily functions" is from 1754.