pre-embryo

https://doi.org/10.1351/goldbook.11115

Fertilized ovum up to \(\pu{14 days}\) of age and before implantation.

Source:
PAC, 2016, 88, 713. (Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)) on page 794 [Terms] [Paper]