blastocyst

[blas-tuh-sist]
noun Embryology.
  1. the blastula of the mammalian embryo, consisting of an inner cell mass, a cavity, and an outer layer, the trophoblast.

Origin of blastocyst

First recorded in 1885–90; blasto- + -cyst
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for blastocyst

blastocyst

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
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

Word Origin and History for blastocyst
n.

1876, from blasto- + cyst.

Online Etymology Dictionary, © 2010 Douglas Harper

blastocyst in Medicine

blastocyst

[blăstə-sĭst′]
n.
  1. The modified blastula stage of mammalian embryos, consisting of the inner cell mass and a thin trophoblast layer enclosing the blastocoel.blastodermic vesicle
Related formsblas′to•cystic adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

blastocyst in Science

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.