of the oral region of a radiate animal, from which the rays or tentacles grow
Origin of actinalactin(o)- + -al
Of, relating to, or located on the part of a radially symmetric animal from which the tentacles radiate or the side where the oral area is found.
- (zoology) Pertaining to the side or surface around the mouth in an animal that has radial symmetry such as a starfish.
- (zoology) Pertaining to the axis of rotational symmetry in radiate animals.
From Ancient Greek ἀκτίς, ἀκτῖν- (actis, actin-, “ray”) + -al. The usage was coined by Louis Agassiz (See quotations below.).