1

fin

play
noun \ˈfin\

Definition of fin

  1. 1 :  an external membranous process of an aquatic animal (such as a fish) used in propelling or guiding the body — see fish illustration

  2. 2 :  something resembling a fin: such asa :  hand, armb (1) :  an appendage of a boat (such as a submarine) (2) :  an airfoil attached to an airplane for directional stabilityc :  flipper 1bd :  any of the projecting ribs on a radiator or an engine cylinder

finlike

play \ˈfin-ˌlīk\ adjective

finned

play \ˈfind\ adjective

Origin and Etymology of fin

Middle English finn, from Old English


2

fin

verb

Definition of fin

finned

;

finning

  1. transitive verb
  2. :  to equip with fins

  3. intransitive verb
  4. 1 :  to show the fins above the water

  5. 2 :  to move through water propelled by fins

First Known Use of fin

1933


3

fin

noun

Definition of fin

slang

  1. :  a 5-dollar bill

Origin and Etymology of fin

Yiddish finf five, from Middle High German, from Old High German — more at five


4

fin

abbreviation

Definition of fin

  1. 1 finance; financial

  2. 2 finish



FIN Defined for Kids

fin

play
noun \ˈfin\

Definition of fin for Students

  1. 1 :  any of the thin parts that stick out from the body of a water animal and especially a fish and are used in moving or guiding the body through the water

  2. 2 :  something shaped like an animal's fin the fins of a missile



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