trophoblast

https://doi.org/10.1351/goldbook.11327

Outer layer of the blastocyst that invades the endometrium and establishes nutrition for the embryo.

Note: Trophoblast cells do not form part of the embryo, but contribute to the development of the placenta.
Source:
PAC, 2016, 88, 713. (Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)) on page 816 [Terms] [Paper]