verb (used with object), finned, fin·ning.

to cut off the fins from (a fish); carve or cut up, as a chub.
to provide or equip with a fin or fins.

verb (used without object), finned, fin·ning.

to move the fins; lash the water with the fins, as a whale when dying.

Origin of fin

before 1000; Middle English, Old English finn; cognate with Dutch vin, Low German finne; akin to Swedish fena
Related formsfin·less, adjectivefin·like, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for finning


abbreviation for



abbreviation for

Finland (international car registration)




any of the firm appendages that are the organs of locomotion and balance in fishes and some other aquatic animals. Most fishes have paired and unpaired fins, the former corresponding to the limbs of higher vertebrates
a part or appendage that resembles a fin
  1. Britisha vertical surface to which the rudder is attached, usually placed at the rear of an aeroplane to give stability about the vertical axisUS name: vertical stabilizer
  2. a tail surface fixed to a rocket or missile to give stability
nautical a fixed or adjustable blade projecting under water from the hull of a vessel to give it stability or control
a projecting rib to dissipate heat from the surface of an engine cylinder, motor casing, or radiator
(often plural) another name for flipper (def. 2)

verb fins, finning or finned

(tr) to provide with fins
(tr) to remove the fins from (a dead fish)
(intr) (esp of a whale) to agitate the fins violently in the water
Derived Formsfinless, adjective

Word Origin for fin

Old English finn; related to Middle Dutch vinne, Old Swedish fina, Latin pinna wing




US slang a five-dollar bill

Word Origin for fin

from Yiddish finf five, ultimately from Old High German funf, finf
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for finning



Old English finn, from Proto-Germanic *finno (cf. Middle Low German vinne, Dutch vin), perhaps from Latin pinna "feather, wing" (see pin (n.)); or, less likely, from Latin spina "thorn, spine" (see spike (n.1)).

U.S. underworld slang sense of "$5 bill" is 1925, from Yiddish finif "five," from German fünf (see five) and thus unrelated. The same word had been used in England 1868 to mean "five pound note" (earlier finnip, 1839).

Online Etymology Dictionary, © 2010 Douglas Harper

Science definitions for finning



One of the winglike or paddlelike parts of a fish, dolphin, or whale that are used for propelling, steering, and balancing in water.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.