fin

1 of 4

noun (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
: 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
d
: any of the projecting ribs on a radiator or an engine cylinder
finlike adjective

fin

2 of 4

verb

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

fin

3 of 4

noun (2)

slang
: a 5-dollar bill

fin

4 of 4

abbreviation

1
finance; financial
2
finish

Word History

Etymology

Noun (1)

Middle English finn, from Old English

Noun (2)

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

First Known Use

Noun (1)

before the 12th century, in the meaning defined at sense 1

Verb

1933, in the meaning defined at transitive sense

Noun (2)

1916, in the meaning defined above

Time Traveler
The first known use of fin was before the 12th century

Dictionary Entries Near fin

Cite this Entry

“Fin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fin. Accessed 4 Dec. 2022.

Kids Definition

fin

noun

ˈfin
1
: a thin process on the outside of an aquatic animal (as a fish or whale) used in propelling or guiding the body
2
: something shaped like a fin
finlike
-ˌlīk
adjective
finned
ˈfind
adjective

More from Merriam-Webster on fin

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