invagination Meaning, Definition & Usage

  1. noun the condition of being folded inward or sheathed
  2. noun the folding in of an outer layer so as to form a pocket in the surface
    infolding; introversion; intussusception.
    • the invagination of the blastula


In*vag`i*na"tion noun
L. pref. in- + vagina sheath.
  1. (Biol.) The condition of an invaginated organ or part.
  2. (Biol.) One of the methods by which the various germinal layers of the ovum are differentiated. ✍ 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.

Webster 1913