Fin(n.)
- An organ of a fish, consisting of a membrane supported by rays, or little bony or cartilaginous ossicles, and serving to balance and propel it in the water.
Fin(n.)
- A membranous, finlike, swimming organ, as in pteropod and heteropod mollusks.
Fin(n.)
- A finlike organ or attachment; a part of an object or product which protrudes like a fin