: any of a genus (family Aplysiidae) of large, sluglike marine gastropod mollusks that lack a shell or have a reduced internal shell embedded in the mantle and that have a pair of lateral winglike extensions on the foot and a pair of sensory tentacles at the front and top of the head

Note: Mollusks of the genus Aplysia feed chiefly on algae and usually discharge a purple ink when threatened. The common name "sea hare" is often used for species of Aplysia and related genera.

The animal he settled on was a lumpy mollusk called Aplysia californica, a large sea snail that you will never see in a wildlife calendar. It looks like a purplish-green baked potato with ears.Stephen S. Hall, New York Times, 15 Feb. 1998

Word History


New Latin, from Greek, a kind of sponge, from aplytos unwashed (from a- a- entry 2 + plytos washed) + -ia; akin to plynein to wash, plein to sail, float, swim

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Dictionary Entries Near Aplysia

Cite this Entry

“Aplysia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Aplysia. Accessed 3 Mar. 2024.

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