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
Northern right whale dolphins are the only dolphin in the North Pacific Ocean to not have a dorsal fin and usually travel in packs of 100 to 200, according to the National Oceanic and Atmospheric Administration.
—Paloma Chavez, Sacramento Bee, 3 Mar. 2025
Another way to distinguish the two is by looking at their dorsal fins.
—Derek Horner, Outdoor Life, 27 Feb. 2025
One of their most striking features is a long, red dorsal fin that runs along their entire body, giving them an almost mythical appearance.
—Dan Perry, Newsweek, 19 Feb. 2025
Northern right whale dolphins are the only dolphin to not have a dorsal fin and usually travel in packs of 100 to 200, according to the National Oceanic and Atmospheric Administration.
—Paloma Chavez, Sacramento Bee, 24 Feb. 2025
Yamamoto thinks they were originally dorsal fin motor neurons that became more specialized.
—Elizabeth Rayne, Ars Technica, 30 Dec. 2024
In contrast, all of a filefish’s dorsal fin motor neurons are located solely in its ventrolateral zone.
—Andrew Paul, Popular Science, 12 Dec. 2024
This appendage is known as the illicium and thought to have once been a dorsal fin.
—Elizabeth Rayne, Ars Technica, 30 Dec. 2024
Within thirty seconds, a dorsal fin emerged, rolling elegantly through the water’s surface like only a bottlenose dolphin can do.
—Essence, 23 Dec. 2024
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Paloma Chavez, Sacramento Bee, 3 Mar. 2025
Another way to distinguish the two is by looking at their dorsal fins.
—Derek Horner, Outdoor Life, 27 Feb. 2025
One of their most striking features is a long, red dorsal fin that runs along their entire body, giving them an almost mythical appearance.
—Dan Perry, Newsweek, 19 Feb. 2025
Northern right whale dolphins are the only dolphin to not have a dorsal fin and usually travel in packs of 100 to 200, according to the National Oceanic and Atmospheric Administration.
—Paloma Chavez, Sacramento Bee, 24 Feb. 2025
Yamamoto thinks they were originally dorsal fin motor neurons that became more specialized.
—Elizabeth Rayne, Ars Technica, 30 Dec. 2024
In contrast, all of a filefish’s dorsal fin motor neurons are located solely in its ventrolateral zone.
—Andrew Paul, Popular Science, 12 Dec. 2024
This appendage is known as the illicium and thought to have once been a dorsal fin.
—Elizabeth Rayne, Ars Technica, 30 Dec. 2024
Within thirty seconds, a dorsal fin emerged, rolling elegantly through the water’s surface like only a bottlenose dolphin can do.
—Essence, 23 Dec. 2024
Articles Related to dorsal fin
Cite this Entry
“Dorsal fin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dorsal%20fin. Accessed 13 Mar. 2025.
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