Meaning

noun an event that occurs at a critical time

verb give occasion to

noun a vaguely specified social event

originFrom Middle English occasioun, from Middle French occasion, from Old French occasiun, from Latin occāsiōnem, noun of action from perfect passive participle occāsus, from verb occidō, from prefix ob- (“down", "away”) + verb cadō (“fall”).

Etymology from Wiktionary, CC BY-SA 3.0