blastocyst

[blas-tuh-sist] /ˈblæs tə sɪst/
noun, Embryology
1.
the blastula of the mammalian embryo, consisting of an inner cell mass, a cavity, and an outer layer, the trophoblast.
Origin
1885-90; blasto- + -cyst
British Dictionary definitions for blastocyst

blastocyst

/ˈblæstəʊˌsɪst/
noun (embryol)
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
Word Origin and History for blastocyst
n.

1876, from blasto- + cyst.

blastocyst in Medicine

blastocyst blas·to·cyst (blās'tə-sĭst')
n.
The modified blastula stage of mammalian embryos, consisting of the inner cell mass and a thin trophoblast layer enclosing the blastocoel. Also called blastodermic vesicle.

blas'to·cys'tic adj.
blastocyst in Science
blastocyst
  (blās'tə-sĭst')   
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.
Encyclopedia Article for blastocyst

a distinctive stage of a mammalian embryo. It is a form of blastula that develops from a berrylike cluster of cells, the morula. A cavity appears in the morula between the cells of the inner cell mass and the enveloping layer. This cavity becomes filled with fluid. The blastocyst differs from the blastula in that it is composed of two already differentiated cell types, the inner cell mass and the enveloping layer

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