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Any of various solitary or colonial sedentary tunicates of the class Ascidiacea, having a sac-shaped body with two siphons. Also called ascidian.
[From its habit of squirting water when disturbed.]
(Animals) any minute primitive marine animal of the class Ascidiacea, most of which are sedentary, having a saclike body with openings through which water enters and leaves. See also ascidian
any of several attached tunicates of the class Ascidiacea, that, on contraction, eject a stream of water.
Any of various primitive sea animals having a transparent, sac-shaped body with two siphons. Sea squirts pump water through the siphons and filter it with gill-like structures to catch food particles. Sea squirts belong to the group known as tunicates.