a. Zool. [f. L. ab away from + -ORAL, f. L. ōr- mouth.] Pertaining to the region of the animal body at the opposite extremity from the mouth. Used especially of those types of animal structure in which the mouth occupies one of the poles.
1857. L. Agassiz, Contrib. Nat. Hist. N. America, IV. 376. I have called this side [of radiate animals] the oral or actinal area, and the opposite side the aboral or abactinal area.
1878. Macalister, Invertebr., 56. The intestine … ends in a small aboral sac or cloaca.
