Source : Webster's Revised Unabridged Dictionary (1913)

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

Source : WordNet®

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