invagination

American  

[in-vaj-uh-ney-shuhn] / ɪnˌvædʒ əˈneɪ ʃən /

noun

1. the act or process of invaginating.

2. Embryology. the inward movement of a portion of the wall of a blastula in the formation of a gastrula.

3. Pathology. intussusception.

4. a form or shape resulting from an infolded tissue.

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invagination British  

/ ɪnˌvædʒɪˈneɪʃən /

noun

1. pathol the process of invaginating or the condition of being invaginated; intussusception

2. pathol an invaginated organ or part

3. an infolding of the outer layer of cells of an organism or part of an organism so as to form a pocket in the surface, as in the embryonic development of a gastrula from a blastula

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Etymology

Origin of invagination

First recorded in 1650–60; invaginate + -ion

Example Sentences

See Examples For:

invagination

The archenteron develops into the alimentary canal, and a mouth opening is formed by invagination of ectoderm at the pole opposite the blastopore of the gastrula.

From Textbooks ● Jan. 1, 2015

White arrow denotes the invagination that forms the shell gland.

From Nature ● Oct. 3, 2012

This bilobed sac becomes entirely the liver in the adult; the intestine and stomach are formed from the pedicle of invagination, whilst the pharynx, oesophagus and crop form from the stomodaeal invagination ph.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 5 "Gassendi, Pierre" to "Geocentric" by Various

There is no open invagination of an archenteron in the fowl, as in the frog--, the gastrula, like the blastosphere, stage is also masked.

From Text Book of Biology, Part 1: Vertebrata by H. G. (Herbert George) Wells

In some cases the inner layer is formed not by invagination but by proliferation or by delamination.

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