zygospherehttp://www.oed.com/dictionary/zygosphere_n%3Ftab%3Dmeaning_and_usezygosphere, n.
First published 1921; not fully revised

zygospherenoun

  1. 1880–
    Either of the two conjugating cells or gametes which form a zygospore.

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

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