blastocyst

[ blas-tuh-sist ]

nounEmbryology.
  1. the blastula of the mammalian embryo, consisting of an inner cell mass, a cavity, and an outer layer, the trophoblast.

Origin of blastocyst

1
First recorded in 1885–90; blasto- + -cyst

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British Dictionary definitions for blastocyst

blastocyst

/ (ˈblæstəʊˌsɪst) /


nounembryol
  1. Also called: blastosphere the blastula of mammals: a sphere of cells (trophoblast) enclosing an inner mass of cells and a fluid-filled cavity (blastocoel)

  2. another name for germinal vesicle

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for blastocyst

blastocyst

[ blăstə-sĭst′ ]


  1. The modified blastula that is characteristic of placental mammals. It has an outer layer, known as a trophoblast, that participates in the development of the placenta. The inner layer of cells develops into the embryo.

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