blastoderm

American  

[blas-tuh-durm] / ˈblæs təˌdɜrm /

noun

Embryology.

1. the primitive layer of cells that results from the segmentation of the ovum.

2. the layer of cells forming the wall of the blastula, and in most vertebrates enclosing a cavity or a yolk mass.

---

blastoderm British  

/ ˈblæstəʊˌdɜːm /

noun

1. the layer of cells that surrounds the blastocoel of a blastula

2. a flat disc of cells formed after cleavage in a heavily yolked egg, such as a bird's egg

---

Other Word Forms

• blastodermatic adjective
• blastodermic adjective

Etymology

Origin of blastoderm

First recorded in 1855–60; blasto- + -derm

Example Sentences

Such words as "blastoderm", "sindoc," "peris," "parasang," "sarcenet," "teazel," "nullah," "cantatrice," "barracan," "sistrum," writhed and hissed in her verses.

From Time Magazine Archive

"Perhaps you'll go and tell her that—you red-headed blastoderm!"

From The City of Numbered Days by Lynde, Francis

The embryo of a moth, a dragon-fly or a bug is invaginated into the yolk at the head end, the portion of the blastoderm necessarily pushed in with it forming the amnion.

From Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 4 "Hero" to "Hindu Chronology" by Various

The rudimentary thorax presents traces of a division into three segments; and the dorso-lateral margins of the cephalic blastoderm, behind the procephalic lobes, have a sinuous margin.

From On the Origin and Metamorphoses of Insects by Lubbock, John, Sir

The origin and development of the blastoderm or germinal disc has nothing to do with recapitulation of the phylogeny.

From Naturalism And Religion by Otto, Rudolf