Biology occurring before fertilization or zygote formation.
ΚΠ
1926 F. A. E. Crew in Q. Rev. Biol.1 341 The action of the Y-borne genes is prezygotic.
1997 G. S. Helfman et al. Diversity of Fishes xxiii. 408/2 Parental care is often distinguished as prezygotic (e.g., nest preparation) and postzygotic (e.g., internal brooding, guarding young).