Meaning

noun the cardinal number that is the sum of four and one

verb equip (a car) with fins

noun one of a pair of decorations projecting above the rear fenders of an automobile

originFrom Middle English fin, from Old English finn, from Proto-Germanic *finnō, *finǭ (“dorsal fin”) (compare Dutch vin, German Finne, Swedish finne, fena), from Proto-Indo-European *(s)pīn- (“backbone, dorsal fin”) (compare Old Irish ind (“end, point”), Latin pinna (“feather, wing, fin”), Tocharian A spin (“hook”).

Etymology from Wiktionary, CC BY-SA 3.0