dorsal fin
noun
plural dorsal fins
: a flat thin body part that projects from the back of many fish (such as trout, barracuda, and sharks) and some marine mammals (such as dolphins)
Porpoises have a more triangular dorsal fin while a dolphin's dorsal fin is more curved.—
Naomi Corrigan and Dave Himelfield
Naomi Corrigan and Dave HimelfieldThis member of the perch family has two dorsal fins and a large mouth outfitted with sharp teeth …—Matt Markey
Matt MarkeyExamples of dorsal fin in a Sentence
Recent Examples on the Web
The baby whale was later identified with a deep gash near its dorsal fin.
—Moná Thomas, PEOPLE, 27 Oct. 2025
This fish, distinguished by its long whisker-like barbels and unique dorsal fin, was found in a small stream within a deep gorge.
—Real-Time News Team, Miami Herald, 26 Sep. 2025
There is nothing quite like the thrill of spotting a dorsal fin slicing through open water or watching a pod leap through the surf beside your boat.
—Alexandra Emanuelli, Southern Living, 18 Sep. 2025
Kikfin says the dorsal fin further improves mobility, helping quickly switch directions by simply turning their head.
—New Atlas, 8 Sep. 2025
The order was withdrawn a week later, but had scientists never tagged the shark’s dorsal fin, it likely wouldn’t have been targeted by this precrime unit.
—Ross Andersen, The Atlantic, 7 Sep. 2025
Sharks are often imagined cruising just beneath the waves, dorsal fin protruding from the dark, ocean waters to alert people of their incoming doom.
—Melissa Cristina Márquez, Forbes.com, 1 Sep. 2025
The video shows the shark's dorsal fin cutting across the water before the giant fish drifts along the side of the kayak, its skin visible just below the surface.
—Soo Kim, MSNBC Newsweek, 29 Aug. 2025
Researchers are able to identify Old Thom based on his very distinct dorsal fin.
—Rick Sobey, Boston Herald, 12 Aug. 2025
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Moná Thomas, PEOPLE, 27 Oct. 2025
This fish, distinguished by its long whisker-like barbels and unique dorsal fin, was found in a small stream within a deep gorge.
—Real-Time News Team, Miami Herald, 26 Sep. 2025
There is nothing quite like the thrill of spotting a dorsal fin slicing through open water or watching a pod leap through the surf beside your boat.
—Alexandra Emanuelli, Southern Living, 18 Sep. 2025
Kikfin says the dorsal fin further improves mobility, helping quickly switch directions by simply turning their head.
—New Atlas, 8 Sep. 2025
The order was withdrawn a week later, but had scientists never tagged the shark’s dorsal fin, it likely wouldn’t have been targeted by this precrime unit.
—Ross Andersen, The Atlantic, 7 Sep. 2025
Sharks are often imagined cruising just beneath the waves, dorsal fin protruding from the dark, ocean waters to alert people of their incoming doom.
—Melissa Cristina Márquez, Forbes.com, 1 Sep. 2025
The video shows the shark's dorsal fin cutting across the water before the giant fish drifts along the side of the kayak, its skin visible just below the surface.
—Soo Kim, MSNBC Newsweek, 29 Aug. 2025
Researchers are able to identify Old Thom based on his very distinct dorsal fin.
—Rick Sobey, Boston Herald, 12 Aug. 2025
Cite this Entry
“Dorsal fin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dorsal%20fin. Accessed 31 Oct. 2025.
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