caudal fin

American  

noun

1. the terminal vertical fin of a fish.

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caudal fin British  

noun

1. the tail fin of fishes and some other aquatic vertebrates, used for propulsion during locomotion

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Example Sentences

They primarily rely on their dorsal fin, whereas strong swimmers use their caudal fin or back tail, Paig-Tran said.

From Los Angeles Times • Nov. 21, 2024

"Additionally, developmental changes suggest that vertebral anatomy shifts across development to support a larger body and caudal fin."

From Science Daily • Jan. 17, 2024

“It’s sort of unreal, when you come around the corner,” he said, looking skyward toward the caudal fin.

From The New Yorker • May 5, 2019

Scaling effects in caudal fin propulsion and the speed of ichthyosaurs.

From Scientific American • Jan. 3, 2012

"The head long, pointed and flat on the top," accords with the pointed extremity and caudal fin of the squid.

From Sea Monsters Unmasked and Sea Fables Explained by Lee, H. W. (Henry William)