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.

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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

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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

The first of these differentiations in time is the formation of the germ-layers, which takes place by a splitting or separation of the blastoderm into a series of superimposed lamellæ.

From Form and Function A Contribution to the History of Animal Morphology by E. S. (Edward Stuart) Russell

C. Bonnet indeed observed in 1745 the virgin-reproduction of Aphids, but it was not until 1842 that R.A. von K�lliker described the formation of the blastoderm in the egg of the midge Chironomus.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 6 "English Language" to "Epsom Salts" by Various

"Are you full awake now, ye red-hot blastoderm?" gasped Graham, struggling to free himself when Gallagher gave him leave.

From Empire Builders by Hambidge, Jay

Pander observed the germinal membrane or blastoderm, as he for the first time called it, of the fowl’s egg to acquire three layers of organized substance in the earlier period of incubation.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 3 "Electrostatics" to "Engis" by Various