late 14c., "success in battle, conquest," also "spiritual victory" and "a procession celebrating victory in war," from Old French triumphe (12c., Modern French triomphe), from Latin triumphus "an achievement, a success; celebratory procession for a victorious general or admiral," from Old Latin triumpus, probably via Etruscan from Greek thriambos "hymn to Dionysus," a loan-word from a pre-Hellenic language.
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<a href="https://www.etymonline.com/word/triumphal">Etymology of triumphal by etymonline</a>
Harper, D. (n.d.). Etymology of triumphal. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/triumphal