fin

The fish's fins minimize water flow.

Then he commenced to talk, really talk. and inside of two flaps of a herring's fin he had me mesmerized, like Eben Holt's boy at the town hall show. He talked about the ills of humanity, and the glories of health and Nature and service and land knows what all.

1913, Joseph C[rosby] Lincoln, chapter IV, in Mr. Pratt’s Patients, New York, N.Y., London: D[aniel] Appleton and Company, →OCLC:

(ichthyology) One of the appendages of a fish, used to propel itself and to manoeuvre/maneuver.

a dolphin's fin

A similar appendage of a cetacean or other marine animal.

The fin stabilises the plane in flight.

A thin, rigid component of an aircraft, extending from the fuselage and used to stabilise and steer the aircraft.

A similar structure protruding from a projectile, used to help keep it on course.

(surfing) A similar structure on the bottom of a surfboard, used to help steer it.

A hairstyle, resembling the fin of a fish, in which the hair is combed and set into a vertical ridge along the top of the head from about the crown to the forehead.

The divers wore fins to swim faster.

A device worn by divers and swimmers on their feet.

An extending part on a surface of a radiator, engine, heatsink, etc., used to facilitate cooling.

A sharp raised edge (generally in concrete) capable of damaging a roof membrane or vapor retarder.

(nautical) The conning tower of a submarine.

flipper

Dutch language
German language
Latin language
Middle English language
Old English language
Old Irish language
Proto-Germanic language
Proto-Indo-European language
Sanskrit language
Swedish language
Tocharian A language
fin
fin (disambiguation)

From 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”), Sanskrit स्फ्य (sphyá, “splinter, staff”).


fin

(transitive) To cut the fins from a fish, shark, etc.

When you spot him finning just under the surface, you move up quietly and present [...] bait, usually a squid.

1983, The Fisherman Who Laughed, page 54:

(intransitive) (Of a fish) to swim with the dorsal fin above the surface of the water.

A neutrally buoyant diver does not need to fin to maintain depth.

(intransitive) To swim in the manner of a fish.

(transitive) To provide (a motor vehicle etc) with fins.

en-verb

fin (third-person singular simple present fins, present participle finning, simple past and past participle finned)

fins (present singular third-person)
finning (participle present)
finned (participle past)
finned (past)


fin

(UK, formerly Australia, slang) a five-pound (£5) note; the sum of five pounds.

(US, slang, dated) a five-dollar bill; the sum of five dollars.

Yiddish language
fin
fin (disambiguation)

From Yiddish פֿינף (finf, “five”). Doublet of five, pimp, and finnuf.


fin

(obsolete, road signs) Denotes the end of the road.

French language
fin
fin (disambiguation)

From French fin (“end”). Doublet of fine and finis.