a membranous, winglike or paddlelike organ attached to any of various parts of the body of fishes and certain other aquatic animals, used for propulsion, steering, or balancing.
Nautical.
a horizontal, often adjustable, winglike appendage to the underwater portion of a hull, as one for controlling the dive of a submarine or for damping the roll of a surface vessel.
Also called vertical stabilizer. Aeronautics. any of certain small, subsidiary structures on an aircraft, designed to increase directional stability.
any of a number of standing ridges on an ordinarily hot object, as a radiator, a cylinder of an internal-combustion engine, etc., intended to maximize heat transfer to the surrounding air by exposing a large surface area.
any part, as of a mechanism, resembling a fin.
Metallurgy. a ridge of metal squeezed through the opening between two rolls, dies, or halves of a mold in which a piece is being formed under pressure.
Automotive. an ornamental structure resembling an aeronautical fin that is attached to the body of an automobile, as on each rear fender tail fin.
Slang. the arm or hand.
Usually fins. flipper.
to cut off the fins from (a fish); carve or cut up, as a chub.
to provide or equip with a fin or fins.
finance.
financial.
finish.
Finland.
Finnish.
finance
financial
any of the firm appendages that are the organs of locomotion and balance in fishes and some other aquatic animals. Most fishes have paired and unpaired fins, the former corresponding to the limbs of higher vertebrates
a part or appendage that resembles a fin
US name: vertical stabilizer. a vertical surface to which the rudder is attached, usually placed at the rear of an aeroplane to give stability about the vertical axis
a tail surface fixed to a rocket or missile to give stability
nautical a fixed or adjustable blade projecting under water from the hull of a vessel to give it stability or control
a projecting rib to dissipate heat from the surface of an engine cylinder, motor casing, or radiator
(often plural) another name for flipper
(tr) to provide with fins
(tr) to remove the fins from (a dead fish)
(intr) (esp of a whale) to agitate the fins violently in the water
Finland
Finnish
First recorded before 1000; Middle English, Old English finn; cognate with Dutch vin, Low German finne; akin to Swedish fena; probably akin to Latin pinna ( def. ); see also pen 1 ( def. )
First recorded in 1865–70; earlier finnip, finnup, fin(n)if “a five-pound note,” from Yiddish fin(e)f “five,” from Middle High German vumf, vimf; see origin at five
A fin is the part of a fish's body that protrudes into the water and helps it balance and move in various directions. Sharks use their dorsal fins to stabilize their bodies as they propel through the water. Fish, whales, dolphins, and other aquatic animals have fins on various parts of their bodies. Surfboards often have a rear fin that works in a similar way, helping to keep the board steady and aid in making turns. Ships, cars, and aircraft also have fins that assist with balance. In Old English, it was finn, which probably comes from the Latin pinna, "feather or wing."
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Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Catcher Dalton Rushing held his hand up to his forehead like a shark fin.
From Los Angeles Times ● Jul. 8, 2026
Tide tables have become the stuff of national interest, and rare moments when the exhausted whale has blown water or flapped its fin have warranted breaking news bulletins.
From Barron's ● Apr. 23, 2026
When GPX4 works properly, it positions a short protein loop -- described as a "fin" -- inside the inner surface of the neuronal membrane.
From Science Daily ● Dec. 9, 2025
The catalog begins with fin de siècle Europe, when the emergence of mass publishing began to lead to a firmer distinction between subordinate illustrators and visionary fine artists.
From The Wall Street Journal ● Nov. 21, 2025
Mrs. Roach held out a languid fin, sighed emphatically and said, “Ah, doctor, so you’ve come at last?”
From "The Once and Future King" by T. H. White
After long observation and many trials they decided that fin. strips of metal screening tacked to the ceiling are what flies like best.
From Time Magazine Archive
“Look at the fin. Floppy on top. It’s not a shark.”
From "Shouting at the Rain" by Lynda Mullaly Hunt
“That’s when I lost part of my tail and cracked my fin. Not a big deal when I’m in fish form, but it’s a bit inconvenient here at Sea Bottom.”
From "When the Sea Turned to Silver" by Grace Lin
IV, 12, ad fin., note, for the statement that he was “Bishop” of Ripon.498.King of Northumbria, v.s. c.
From Bede's Ecclesiastical History of England by Bede, Cuthbert
III, 3, ad fin., note.558.Innisboffin, off the coast of Mayo.
From Bede's Ecclesiastical History of England by Bede, Cuthbert
Moss and Njemile were getting off at the MacArthur station the next morning when Njemile said, “I declare this year over. Fin. Cerrado. Done.”
From "Anger Is a Gift" by Mark Oshiro
“Nothing of the kind,” said Fin., drying his eyes, and endeavouring to look sorry and sentimental.
From Humours of Irish Life by Various
At the same time he is not a mere translator: de Fin. i.
From The Student's Companion to Latin Authors by Middleton, George
Fin. iv. 14; defendere, an actual 215 attack, as to defend, in opp. to deserere.
From Döderlein's Hand-book of Latin Synonymes by Döderlein, Ludwig
In the Hortensius Cicero appeared as the champion of philosophy: De Fin. i.
From The Student's Companion to Latin Authors by Middleton, George
“We figured out a day before we started shooting that these things don’t quite marry up,” said Johnstone, who turned to FIN Design and Effects of Australia to blend his M3GANs together.
From Los Angeles Times ● Jan. 7, 2023
USA 1-0 FIN 20:00 That’s the end of the period — the goal from defenseman Faulk, a Carolina prospect who now plays for Minnesota-Duluth, is all the scoring in a relatively tame opening stanza.
From New York Times ● Dec. 27, 2010
USA 3-2 FIN … two points for the Amerks, one for the Finns.
From New York Times ● Dec. 27, 2010
In fact, "Breathless" is dedicated to Monogram Pictures, an American studio that specialized in grade-B crime dramas, and carries no other credits: only the title at the beginning and the word "FIN" at the end.
From Salon ● May 29, 2010
I have often indeed heard the saying, On peut etre plus FIN qu'un autre, mais pas plus FIN que tous les autres.
From Life of John Sterling by Carlyle, Thomas
Fin Smith had already attempted a crossfield kick to Northampton team-mate Tommy Freeman from an early penalty, only to be called back by referee Hollie Davidson for going too quickly.
From BBC ● Jul. 11, 2026
Last week, Salesforce announced the acquisition of customer-agent company Fin for roughly $3.6 billion, further stoking investor discontent.
From MarketWatch ● Jun. 22, 2026
In a move to bolster its business offerings and assuage investor concerns about AI making some software offerings obsolete, Salesforce said it had agreed to acquire Fin, formerly known as Intercom.
From Barron's ● Jun. 15, 2026
This is where Fin fits in to Salesforce’s AI strategy.
From Barron's ● Jun. 15, 2026
Fin went to pick it up and asked, “Do you think Kaihan objected to his marriage?”
From "Huntress" by Malinda Lo
Matthews said the device actually contained "a load of cardboard fins that get wet as the water blows past them".
From BBC ● Jul. 10, 2026
The drum of an arena would be surrounded by an elegant rectangular box with vertical fins and tall windows.
From The Wall Street Journal ● Jun. 13, 2026
Their fins are accented with orange, and they possess a smaller oval tooth patch.
From Science Daily ● Mar. 23, 2026
“For the first time since automobiles had fins, the world stands in awe of a car from the United States,” the automotive enthusiast magazine Road & Track raved in a 2012 review.
From MarketWatch ● Jan. 29, 2026
On its back were feathery fins that shimmered in the light.
From "The Wild Robot Protects" by Peter Brown
The first lobe finned fish that developed limbs capable of supporting movement on land still relied heavily on aquatic environments.
From Science Daily ● Feb. 11, 2026
Magnus wrote in his 1555 book they were 200-feet long with broad, forked tails and finned feet, with faces resembling warthogs and dual blow-holes on the top of their heads.
From National Geographic ● Dec. 28, 2023
Large finned automobiles that resemble 1950s classics hover over smooth roads, as do baby carriages across perfectly clean sidewalks in perfectly manicured suburbs.
From Los Angeles Times ● Feb. 17, 2023
State media released a photo of a missile mounted with a finned, cone-shaped payload soaring into the air while leaving a trial of bright orange flames.
From Seattle Times ● Sep. 28, 2021
The minute he got his hands on it, the fish finned him and he went to crying.
From "Old Yeller" by Fred Gipson
But regulations that have reduced the frequency of finning have not saved shark lives, an international research team reports in the journal Science this week.
From National Geographic ● Jan. 11, 2024
A global onslaught of legislation followed to limit shark catch-and-eliminate finning, widely regarded as a cruel and wasteful fishing method.
From Science Magazine ● Jan. 10, 2024
The practice, called finning, leaves the fish unable to swim and survive.
From Washington Post ● Dec. 15, 2022
He said few in the U.S. are involved in the cruel, wasteful practice of shark finning and that the U.S.’ role as a transit hub for fins can be remedied without punishing American fishers.
From Seattle Times ● Aug. 2, 2022
"Headin' straight out to sea when dry ground's off that way," said Murray, finning feeble hand to starboard, "ain't what Dan'l Webster would do, with his intellect, if he was here."
From The Skipper and the Skipped Being the Shore Log of Cap'n Aaron Sproul by Day, Holman
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
