dorsal fin

noun

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

dorsal fin

noun

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

Word History and Origins

Origin of dorsal fin¹

First recorded in 1760–70

Example Sentences

They crawled around blowholes and dorsal fins, and soon each human was sitting on the back of their very own whale.

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Each encounter was carefully recorded, and the individual orcas were identified by markings on their dorsal fins.

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"A dorsal fin slowly broke the surface revealing that familiar profile that looked like a shark," he said.

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He thrust the blade into the thick muscle beneath the dorsal fin to attach the tracking device.

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Winter had put a life vest on the dog resembling a shark, with a dorsal fin protruding from its back.

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