dorsal fin


noun

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

Origin of dorsal fin

First recorded in 1760–70

Example sentences from the Web for dorsal fin

  • In the figure there is represented the cross-section of a fish (its dorsal-fin D) just before the spear strikes.

    Along Alaska's Great River |Frederick Schwatka

British Dictionary definitions for dorsal fin

dorsal fin

noun

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