or blas·to·disc

[ blas-tuh-disk ]
/ ˈblæs təˌdɪsk /

noun Embryology.

the blastula that forms as a flattened sphere on top of the yolk in the yolk-laden eggs of birds and reptiles.

Origin of blastodisk

First recorded in 1885–90; blasto- + disk Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for blastodisc


/ (ˈblæstəʊˌdɪsk) /


another name for blastoderm
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

Medicine definitions for blastodisc



The disk of active cytoplasm at the animal pole of a telolecithal egg.
The blastoderm, especially in very early stages when its extent is small.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.