FINS

noun

1. One of the appendages of a fish, used to propel itself and to manoeuvre/maneuver.
2. A similar appendage of a cetacean or other marine animal.
3. A thin, rigid component of an aircraft, extending from the fuselage and used to stabilise and steer the aircraft.

verb

1. To cut the fins from a fish, shark, etc.
2. (Of a fish) to swim with the dorsal fin above the surface of the water.
3. To swim in the manner of a fish.

noun

1. (formerly Australia) a five-pound (£5) note; the sum of five pounds.
2. A five-dollar bill; the sum of five dollars.