Isocephalism \I`so*ceph"a*lism\, n. [From Gr. ? like-headed. See {Iso-}, and {Cephalon}.] (Art) A peculiarity in the design of bas-relief by which the heads of human figures are kept at the same height from the ground, whether the personages are seated, standing, or mounted on horseback; -- called also {isokephaleia}.