zy·go·mor·phic (z??g?-môr?f?k, z?g??-) also zy·go·mor·phous (-f?s)adj. Botany Having bilateral symmetry, as the flowers of a pea plant.zy?go·mor?phy n.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.zygomorphic (?za?????m??f?k; ?z??-) or zygomorphousadj (Botany) (of a flower) capable of being cut in only one plane so that the two halves are mirror images. See also actinomorphic ?zygo?morphism, ?zygo?morphy nCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014