Fin

fin, n. the organ by which a fish balances itself and swims.— n. Fin′-back , a finner or fin-whale.— adjs. Fin′-foot′ed , having feet with toes connected by a membrane; Finned , having fins; Fin′ny , furnished with fins.— n. Fin′-ray , one of the rods or rays supporting a fish's fin.— adj. Fin′-toed , having feet with membranes connecting the toes, as aquatic birds. [A.S. finn ; L. pinna , a fin.]