tail fin



Automotive. See under fin1(def 7).

Nearby words

  1. tail coat,
  2. tail cone,
  3. tail covert,
  4. tail end,
  5. tail fan,
  6. tail fold,
  7. tail gate,
  8. tail off,
  9. tail out,
  10. tail plane

Origin of tail fin

First recorded in 1675–85


[ fin ]
/ fɪn /


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

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for tail fin

British Dictionary definitions for tail fin


abbreviation for



abbreviation for

Finland (international car registration)


/ (fɪn) /


verb fins, finning or finned

Derived Formsfinless, adjective

Word Origin for fin

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


/ (fɪn) /


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 tail fin



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 tail fin


[ fĭn ]

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.