The Collaborative International Dictionary of English v.0.48:
Homomorphy \Ho"mo*mor`phy\, n. [Homo- + Gr. morfh` form.] (Biol.) Similarity of form; resemblance in external characters, while widely different in fundamental structure; resemblance in geometric ground form. See Homophyly, Promorphology. [1913 Webster]WordNet (r) 3.0 (2006):
homomorphy n 1: similarity of form [syn: homomorphism, homomorphy]