A'cri-tā or A'cri-tan, n.

n. [Gr. ἄκριτος, undistinguished, indiscernible, from ἀ priv. and κρίνειν, to distinguish.] (Zoöl.) That division of radiate animals and the Protozoa, in which there is no distinct nervous system, as the sponges, polyps, &c. Dana.