Origin of germinal disk
First recorded in 1875–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
A flattened, disklike region of cells from which the embryo develops in the fertilized ovum of many vertebrate species.embryonic disk
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.