What is "actinal"

Actinal \Ac"ti*nal\, a. [Gr. ?, ?, ray.] (Zo["o]l.) Pertaining to the part of a radiate animal which contains the mouth.
--L. Agassiz. [1913 Webster] ||

a. 1 (context zoology English) Pertaining to the side or surface around the mouth in an animal that has radial symmetry such as a starfish. 2 (context zoology English) Pertaining to the axis of rotational symmetry in radiate animals.

adj. (of radiate organisms) located on the surface or end on which the mouth is situated [ant: abactinal]