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

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

From Science Daily

"They work in tandem to utilize the reverse-Kármán vortex street and adjust their caudal fins accordingly."

From Science Daily

I gave it a strong caudal fin—a tail—to allow the shark to swim side to side and propel it forward.

From Literature

Thresher sharks are known as quick swimmers with small mouths, long caudal fins and timid dispositions, according to the Florida Museum of Natural History.

From Fox News

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

From The New Yorker