Is it ensure, insure, or assure?
late 15c., from Middle French nuptial, or directly from Latin nuptialis "pertaining to marriage," from nuptiae "wedding," from nupta, fem. past participle of nubere "to marry, wed, take as a husband," related to Greek nymphe "bride," from PIE *sneubh- "to marry, wed" (cf. Old Church Slavonic snubiti "to love, woo," Czech snoubiti "to seek in marriage," Slovak zasnubit "to betroth"). Related: Nuptially.