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
Other anglers prefer tube jigs or a jig with a tiny minnow impaled through its dorsal fin.
—Cory Schmidt, Outdoor Life, 15 Apr. 2026
But when a wall of water crashes through the windows, turning the living room into a swimming pool that’s soon crawling with dorsal fins, the kids are left to fend for themselves.
—David Rooney, HollywoodReporter, 10 Apr. 2026
Right whales, with their characteristic drooping dorsal fin, are most often seen along the Eastern Seaboard, but over the past few years two of them were spotted in the Gulf, one with a calf.
—Orlando Sentinel Editorial Board, The Orlando Sentinel, 8 Apr. 2026
One of the largest great white sharks tagged by scientists along the East Coast is lingering off North Carolina for reasons that aren’t quite clear, according to a tracker fitted to its dorsal fin.
—Mark Price, Charlotte Observer, 11 Feb. 2026
And the tracking device attached to his dorsal fin is helping researchers uncover secrets about the elusive apex predator.
—Bill Kearney, Sun Sentinel, 22 Jan. 2026
Giles examined the fins and saddle patches (a swirly white marking behind the dorsal fin) to identify these whales as part of J-pod.
—Kelso Harper, Scientific American, 16 Dec. 2025
The most notable additions to the exterior are the air intake on the roof, the carbon-fiber dorsal fin, the enlarged rear wing, and a new hood.
—Viju Mathew, Robb Report, 17 Nov. 2025
Moctezuma’s pod was identified by the distinct markings on the orcas’ dorsal fins.
—Aamir Khollam, Interesting Engineering, 3 Nov. 2025
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Cory Schmidt, Outdoor Life, 15 Apr. 2026
But when a wall of water crashes through the windows, turning the living room into a swimming pool that’s soon crawling with dorsal fins, the kids are left to fend for themselves.
—David Rooney, HollywoodReporter, 10 Apr. 2026
Right whales, with their characteristic drooping dorsal fin, are most often seen along the Eastern Seaboard, but over the past few years two of them were spotted in the Gulf, one with a calf.
—Orlando Sentinel Editorial Board, The Orlando Sentinel, 8 Apr. 2026
One of the largest great white sharks tagged by scientists along the East Coast is lingering off North Carolina for reasons that aren’t quite clear, according to a tracker fitted to its dorsal fin.
—Mark Price, Charlotte Observer, 11 Feb. 2026
And the tracking device attached to his dorsal fin is helping researchers uncover secrets about the elusive apex predator.
—Bill Kearney, Sun Sentinel, 22 Jan. 2026
Giles examined the fins and saddle patches (a swirly white marking behind the dorsal fin) to identify these whales as part of J-pod.
—Kelso Harper, Scientific American, 16 Dec. 2025
The most notable additions to the exterior are the air intake on the roof, the carbon-fiber dorsal fin, the enlarged rear wing, and a new hood.
—Viju Mathew, Robb Report, 17 Nov. 2025
Moctezuma’s pod was identified by the distinct markings on the orcas’ dorsal fins.
—Aamir Khollam, Interesting Engineering, 3 Nov. 2025
Cite this Entry
“Dorsal fin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dorsal%20fin. Accessed 19 Apr. 2026.
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