Is it ensure, insure, or assure?
late 14c., from Old French triumphe (12c.), from Latin triumphus "achievement, a success, procession for a victorious general or admiral," earlier triumpus, probably via Etruscan from Greek thriambos "hymn to Dionysus," a loan-word from a pre-Hellenic language. Sense of "victory, conquest" is c.1400.
late 15c.; see triumph (n.). Related: Triumphed; triumphing.