'Invagination' definitions:
Definition of 'invagination'
From: WordNet
noun
The condition of being folded inward or sheathed [syn: invagination, introversion]
noun
The folding in of an outer layer so as to form a pocket in the surface; "the invagination of the blastula" [syn: invagination, introversion, intussusception, infolding]
Definition of 'Invagination'
From: GCIDE
- Invagination \In*vag`i*na"tion\, n. [L. pref. in- + vagina sheath.] [1913 Webster]
- 1. (Biol.) The condition of an invaginated organ or part. [1913 Webster]
- 2. The inward movement of the wall of a tissue or cell, to form a cavity; also, the cavity thus formed. [PJC]
- 3. Specifically: (Biol., Embryology) The inward movement of one part of the wall of a blastula, to form a gastrula; the process of gastrulation, in which layers of the ovum are differentiated. [1913 Webster +PJC]
- Note: In embolic invagination, one half of the blastosphere is pushed in towards the other half, producing an embryonic form known as a gastrula. -- In {epibolic invagination}, a phenomenon in the development of some invertebrate ova, the epiblast appears to grow over or around the hypoblast. [1913 Webster]