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 absence of metamorphosis here may perhaps be due to the fact that the lateral fins ceased to function in the earlier aquatic stages, only the caudal fin being used for swimming.

From Hormones and Heredity by Cunningham, J. T.