First Known Use: before 12th century
Dictionary
1fin
noun \ˈfin\
Definition of FIN
1
: an external membranous process of an aquatic animal (as a fish) used in propelling or guiding the body — see fish illustration
2
: something resembling a fin: as a : hand, arm b (1) : an appendage of a boat (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
— fin·like \-ˌlīk\ adjective
— finned \ˈfind\ adjective
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Origin of FIN
Middle English finn, from Old English
Other Anatomy Terms
2fin
verb
finnedfin·ning
Definition of FIN
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
3fin
noun
Definition of FIN
slang : a 5-dollar bill
Origin of FIN
Yiddish finf five, from Middle High German, from Old High German — more at five
First Known Use: 1916
4fin
abbreviation
Definition of FIN
1
finance; financial
2
finish
FIN Defined for Kids
fin
noun \ˈfin\
Definition of FIN for Kids
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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