from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The outermost layer of cells of the blastocyst that attaches the fertilized ovum to the uterine wall and serves as a nutritive pathway for the embryo. Also called trophoderm.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. 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.
from The Century Dictionary and Cyclopedia
- n. An external epiblastic layer that does not enter into the formation of the embryo, but does take an active part in nutritional processes intended for it; the blastocystic ectoderm.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the membrane that forms the wall of the blastocyst in early development; aids implantation in the uterine wall
tropho- + -blast (Wiktionary)