dorsal fin

American  

noun

1. the fin or finlike integumentary expansion generally developed on the back of aquatic vertebrates.

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dorsal fin British  

noun

1. any unpaired median fin on the backs of fishes and some other aquatic vertebrates: maintains balance during locomotion

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Etymology

Origin of dorsal fin

First recorded in 1760–70

Example Sentences

See Examples For:

dorsal fin

“I never thought I’d be holding the dorsal fin of a great white shark and applying this type of technology,” Michalove said.

From Seattle Times ● May 23, 2024

The researchers call transients Orcinus rectipinnus, noting that, in Latin, “recti means right or upright, and pinna means fin, feather, or wing, most likely referring to the tall erect dorsal fin of males.”

From Los Angeles Times ● Mar. 29, 2024

What they spotted, a whale without a dorsal fin, led the researchers to think that it might be a North Atlantic right whale, a critically endangered species that the aquarium has been closely monitoring.

From New York Times ● Mar. 6, 2024

And unlike other mosasaurs, or large extinct marine reptiles, it had a dorsal fin like a shark's that would have helped it turn quickly and with precision in the water.

From Science Daily ● Dec. 12, 2023

Fred pointed to a small chunk missing from the dorsal fin.

From "The Line Tender" by Kate Allen