neu·ro·gen·e·sis (no?or??-j?n??-s?s, nyo?or?-)n. pl. neu·ro·gen·e·ses (-s?z?) Formation of nervous tissue.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.neurogenesis (?nj??r???d??n?s?s) n (Physiology) embryol the formation of the nervous system in embryosCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014