Related to hypogenous: hypogynous
Growing on a lower surface of a structure, as fungi on leaves.
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.
(Botany) botany produced or growing on the undersurface, esp (of fern spores) growing on the undersurface of the leaves
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014