[1] : The Collaborative International Dictionary of English v.0.48

invagination \invag`ina"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
see also:
embolic invagination epibolic invagination 

[2] : WordNet (r) 2.0

invagination
     n 1: the condition of being folded inward or sheathed syn: introversion
     2: the folding in of an outer layer so as to form a pocket in
        the surface; "the invagination of the blastula" syn: introversion,
         intussusception, infolding
see also:
introversion intussusception infolding 

Invagination >> I Words
Invagination, definition of term: Invagination
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