Definition of "oogenesis" [o•ö•gen•e•sis]

• The formation, development, and maturation of an ovum. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "This marine worm, first described in 1949 as an acoel flatworm and later claimed as either an early metazoan offshoot or a primitive deuterostome, has recently been affiliated with primitive bivalve molluscs, based upon a study of gamete development oogenesis and an analysis of sequence data from both 18S rRNA and mitochondrial genes."
• "Since the shell is secreted by the follicle cells during oogenesis, we expected the defect to depend on the genotype of those cells."
• "Drosophila oogenesis to come to rival embrogenesis as a ideal system for studying patterning."