dorsal fin

One of one or more unpaired fins on the back of fishes and certain marine mammals.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

dorsal fin

(Zoology) any unpaired median fin on the backs of fishes and some other aquatic vertebrates: maintains balance during locomotion

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

ThesaurusAntonymsRelated WordsSynonymsLegend:

Noun

dorsal fin - unpaired median fin on the backs of fishes and some other aquatic vertebrates that help to maintain balance

fin - organ of locomotion and balance in fishes and some other aquatic animals

Translations

selkäevä

nageoire dorsale

bakuggi

dorsal fin

n → Rückenflosse f

Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007

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References in classic literature

Nor did he see the dorsal fin break surface and approach him from the rear.

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Kidd could see the finger of the dial stand up dark against the sky like the dorsal fin of a shark and the vain moonlight clinging to that idle clock.

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This same fish has the power of firmly catching hold of any object, such as the blade of an oar or the fishing- line, with the strong spine both of its pectoral and dorsal fin. In the evening the weather was quite tropical, the thermometer standing at 79 degs.

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Great slate-colored backs and high serrated dorsal fins shot up with a fringe of silver, and then rolled down into the depths again.

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Enolva said the 4.91-meter mammal was found at Sitio Bongsanglay in Gibraltar village with a rope around its dorsal fin and wounds on its tail, which possibly caused its death.

Thin, wounded whales found dead in Bicol shores

They were able to identify one of the dolphins, nicknamed Mischief, in the Netherlands earlier this month due to scars on its dorsal fin.

Dolphin sightings recorded

John Power, who spotted it, said: "We sighted a dorsal fin unlike anything we had encountered.

Hammer headed here; Tropical shark is seen in UK waters

But the film appears to show some bodies with the dorsal fin removed.

Illegal finning fears as dead sharks washed up

The dorsal fin of a shark breaking through the water in America

Up to 100 sharks wash up DEAD on beach sparking fears their fins were ripped off; Marine conservationists fear the fish were victims of shark finning, meaning their dorsal fins were ripped off and they were thrown back into the sea

"We attract the sharks using a line baited with a tuna head or a seal-shaped decoy, and then -- when a shark closes in for a look -- we use a pole to clamp the tag to the dorsal fin," Jewell explained.

Reality TV: Camera-toting sharks hunt seals in kelp forests

Disc wider than long, margins of pectoral fins broadly rounded; anterior lobe of pelvic fins slender, pointed; tail longer than disc; snout soft, flexible, especially near tip, internal supporting rostral cartilage slender and weak; teeth small, numerous, 32 rows in upper jaw; interorbital space wide, slightly convex; thorns absent from disc; tail thorns 29, interdorsal thorns 2; dorsal and ventral surface of head and body uniformly covered with small denticles; 2 small, well-separated dorsal fins, about equal in height and length; predorsal vertebrae between pelvic girdle and origin of first dorsal fin about 86.

RANGE EXTENSIONS AND NEW RECORDS FROM ALASKA AND BRITISH COLUMBIA FOR TWO SKATES, BATHYRAJA SPINOSISSIMA AND BATHYRAJA MICROTRACHYS

Caption: Thomas ensures the inner surface of the dorsal fin is clean and ready for rib installation.

Additive Manufacturing, Collaboration: KEEP T-6Bs FLYING: The recent delivery of 15 T-6B Texan II dorsal assembly ribs in a matter of weeks is an example of how quickly stakeholders can increase readiness through collaboration and innovation