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
This member of the perch family has two dorsal fins and a large mouth outfitted with sharp teeth …Matt Markey

Examples of dorsal fin in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
From the Remo flounder to the anglerfish to the suckerfish, dorsal fin modifications provide insight into how fish evolve to fit their needs. Katie Cottingham, Smithsonian Magazine, 9 Sep. 2024 But are these fascinating appendages really dorsal fins? Katie Cottingham, Smithsonian Magazine, 9 Sep. 2024 Winter had put a life vest on the dog resembling a shark, with a dorsal fin protruding from its back. Ian James, Los Angeles Times, 9 Oct. 2024 The scientists also discovered signs of orca tooth rake marks on the dorsal fin of a fin whale (Balaenoptera physalus). Mindy Weisberger, CNN, 26 Sep. 2024 Some of my most memorable topwater hits have started with that big dorsal fin slicing the surface as a bull mahi charges my popper. Joe Cermele, Outdoor Life, 19 Sep. 2024 From the exterior, each F5-M will be easily identifiable thanks to a 55-inch dorsal fin that extends from the rear of the intake scoop on the roof. Michael Van Runkle, Robb Report, 10 Sep. 2024 As a fish swims through water, the dorsal fin stabilizes it and keeps it from rolling over. Katie Cottingham, Smithsonian Magazine, 9 Sep. 2024 Tracking tags were placed on the dorsal fins of the sharks and used to collect information on water depth and temperature. Mary Cunningham, CBS News, 3 Sep. 2024

Word History

First Known Use

1752, in the meaning defined above

Time Traveler
The first known use of dorsal fin was in 1752

Dictionary Entries Near dorsal fin

Cite this Entry

“Dorsal fin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dorsal%20fin. Accessed 10 Nov. 2024.

Kids Definition

dorsal fin

noun
: a fin on the ridge along the middle of the back of a fish or sea mammal (as a whale)
Last Updated: - Updated example sentences
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