as·​cid·​i·​an ə-ˈsi-dē-ən How to pronounce ascidian (audio)
: any of a class (Ascidiacea) of solitary or colonial sessile tunicates having an incurrent and excurrent siphon

called also sea squirt

Word History


New Latin Ascidia, group comprising tunicates, from Ascidium, genus name, from Greek askidion, diminutive of askos wineskin, bladder

First Known Use

1823, in the meaning defined above

Time Traveler
The first known use of ascidian was in 1823

Dictionary Entries Near ascidian

Cite this Entry

“Ascidian.” Dictionary, Merriam-Webster, Accessed 23 Jun. 2024.

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