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

Caudal fin low, bluntly rounded posteriorly; greatest depth of caudal musculature about one-half depth of caudal fin; musculature extends nearly to tip of tail.

From A Review of the Middle American Tree Frogs of the Genus Ptychohyla by Duellman, William E.