When the word opportunity was first borrowed into the English language in 1387, it was spelled oportunite, and other forms around the time included oportunyte, oportewnyte, oportunyty, oppertunitie, and more. The noun was taken from Old French, where it also showed up as oportunite. That was borrowed in the thirteenth century from Latin opportunitas, meaning "fitness" or "convenience". Opportunitas is from the adjective opportunas ("fit" or "favorable"), which derived from the phrase ob portum veniens, meaning "coming toward a port". The idea was that a wind blowing toward a harbor was favorable or convenient for ships trying to get to the shore. You might know ob- from words like obscene, oppress, and obstruct: it comes from Proto-Indo-European opi, meaning "against". Finally, portus, the nominative of portum, comes from PIE prtu and veniens traces to PIE gwa, "to go".
Hello! I'm Adam Aleksic, a senior studying government and linguistics at Harvard University, where I co-founded the Harvard Undergraduate Linguistics Society. In addition to etymology, I also really enjoy trivia, politics, vexillology, geography, board games, conlanging, art history, and law.