1

fin

noun \ ˈfin \

Definition of fin

1 :an external membranous process of an aquatic animal (such as a fish) used in propelling or guiding the body — see fish illustration
2 :something resembling a fin: such as
a :hand, arm
b (1) :an appendage of a boat (such as a submarine)
(2) :an airfoil attached to an airplane for directional stability
c :flipper 1b
d :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
transitive verb
:to equip with fins
intransitive verb
1 :to show the fins above the water
2 :to move through water propelled by fins

First Known Use of fin

1933


3

fin

noun

Definition of fin

slang
: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 finance; financial
2 finish


FIN Defined for Kids

fin

noun \ ˈfin \

Definition of fin for Students

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


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