Trophoblast
WordNet
noun
(1) The membrane that forms the wall of the blastocyst in early development; aids implantation in the uterine wall
"After implantation of the blastocyst in the uterine wall the trophoblast divides into two layers, the chorion and the placenta"
WiktionaryText
Noun
- The membrane of cells that forms the wall of a blastocyst during early pregnancy, providing nutrients to the embryo and later developing into part of the placenta.