The story
- Latin · borrowed fromquīndecennālia
- English todayquindecennalia
From Latin quīndecennālia, from quīndecennium (“15-year period”) + -ālia (“-alia: forming the names of festivals”), from quīndecennis (“15-year”) + -ium (“-ium: forming abstract nouns”). Equivalent to quin- + decennalia, quindec- + Latin ennalia, or Latin quindecennium + -alia.
Etymology from Wiktionary, CC BY-SA 4.0.