Word Study
ascidian
CIDE DICTIONARY
ascidian, n. [Gr. bladder, pouch.].
One of the Ascidioidea, or in a more general sense, one of the Tunicata. Also as an adj. [1913 Webster]
OXFORD DICTIONARY
ascidian, n. Zool. any tunicate animal of the class Ascidiacea, often found in colonies, the adults sedentary on rocks or seaweeds, e.g. the sea squirt.
Etymology
mod.L Ascidia f. Gk askidion dimin. of askos wineskin
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