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

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

White arrow denotes the invagination that forms the shell gland.

From Nature • Oct. 3, 2012

The preconchylian invagination or shell-gland is formed in the embryo behind the velum, on the surface opposite the blastopore.

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

The difference is evidently entirely due to the presence of yolk, and the consequent modification of invagination in the former case.

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