I. ˈfin noun
Etymology: Middle English finn, from Old English
Date: before 12th century
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
II. verb
( finned ; fin·ning )
Date: 1933
transitive verb
: to equip with fins
intransitive verb
1. : to show the fins above the water
2. : to move through water propelled by fins
III. noun
Etymology: Yiddish finf five, from Middle High German, from Old High German — more at five
Date: 1916
slang : a 5-dollar bill
IV. abbreviation
1. finance; financial
2. finish