Try Our Apps


Supposedly vs. Supposably


[blas-tuh-sist] /ˈblæs tə sɪst/
noun, Embryology
the blastula of the mammalian embryo, consisting of an inner cell mass, a cavity, and an outer layer, the trophoblast.
Origin of blastocyst
1885-90; blasto- + -cyst Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
Cite This Source
British Dictionary definitions for blastocyst


noun (embryol)
Also called blastosphere. the blastula of mammals: a sphere of cells (trophoblast) enclosing an inner mass of cells and a fluid-filled cavity (blastocoel)
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
Cite This Source
Word Origin and History for blastocyst

1876, from blasto- + cyst.

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
blastocyst in Medicine

blastocyst blas·to·cyst (blās'tə-sĭst')
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.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
blastocyst in Science
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 © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source

Word of the Day

Difficulty index for blastocyst

Some English speakers likely know this word

Word Value for blastocyst

Scrabble Words With Friends

Nearby words for blastocyst