embryonic disk

American  

[em-bree-on-ik disk] / ˈɛm briˌɒn ɪk ˈdɪsk /

noun

Embryology.

1. Also called embryonic shield.  in the early embryo of mammals, the flattened inner cell mass that arises at the end of the blastocyst stage and from which the embryo begins to differentiate.

2. the blastodisk of yolky eggs.

---

Etymology

Origin of embryonic disk

First recorded in 1935–40

Example Sentences

See Examples For:

embryonic disk

Roughly two weeks after fertilization, more than half of the embryos had an embryonic disk — a flat mass of cells.

From Scientific American ● May 15, 2023

Transverse section of the embryonic disk of a chick at the end of the first day of incubation, magnified about twenty times.

From The Evolution of Man — Volume 1 by Haeckel, Ernst Heinrich Philipp August

Sole-shaped embryonic disk of the chick, in three successive stages of development, looked at from the dorsal surface, magnified about twenty times, somewhat diagrammatic.

From The Evolution of Man — Volume 1 by Haeckel, Ernst Heinrich Philipp August

At the beginning of germination the flat embryonic disk curves outwards, and separates on the inner side from the underlying large yelk-ball.

From The Evolution of Man — Volume 1 by Haeckel, Ernst Heinrich Philipp August

Three diagrammatic transverse sections of the embryonic disk of the higher vertebrate, to show the origin of the tubular organs from the bending germinal layers.

From The Evolution of Man — Volume 1 by Haeckel, Ernst Heinrich Philipp August