tail fan

American  

noun

Zoology.

1. the fanlike posterior appendage of crayfish and lobsters, consisting of a telson and two uropods, used for rapid backward propulsion.

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tail fan British  

noun

1. the fanned structure at the hind end of a lobster or related crustacean, formed from the telson and uropods

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Etymology

Origin of tail fan

First recorded in 1890–95

Example Sentences

As it undulated through an ancient sea with its flaps and spiky tail fan, Utaurora likely wielded its proboscis to shovel food into its mouth.

From New York Times • Feb. 8, 2022

The tail fan closes and droops, the wings fall, the ruffs smooth down.

From Some Summer Days in Iowa by Lazell, Frederick John

Set the legs in their permanent position, spread or close the tail fan as desired, arrange the antennae, and set the specimen in a well ventilated spot to dry.

From Taxidermy by Pray, Leon Luther