1690s, "treat with indulgence and affection" (now obsolete), from fond (adj.) + frequentative ending. Or possibly from the obsolete verb fond "be fond, be in love, dote" (1520s), from the adjective or altered from earlier fon. Sense of "caress" first recorded 1796. As a noun from 1833. Related: Fondled; fondling (1670s as a past-participle adjective); fondlesome.