zygogenesishttp://www.oed.com/dictionary/zygogenesis_n%3Ftab%3Dmeaning_and_usezygogenesis, n.
First published 1986; not fully revised

zygogenesisnoun

  1. 1950–
    Reproduction involving the formation of a zygote.
    1. 1950
      The most common mode of animal reproduction is, however, sexual reproduction or gamogony or zygogenesis.
      Adv. Genetics vol. 3 194
    2. 1973
      It [sc. random genetic drift] includes all events that lead to sampling error in random zygogenesis.
      B. J. Williams, Evolution & Human Origins iii. 37/2

Originally published as part of the entry for zygo-, comb. form

zygo-, comb. form was first published in 1921; not fully revised.