The Collaborative International Dictionary of English v.0.48:

Introsusception \In`tro*sus*cep"tion\, n.
   1. The act or process of receiving within.
      [1913 Webster]

            The person is corrupted by the introsusception of a
            nature which becomes evil thereby.    --Coleridge.
      [1913 Webster]

   2. (Med.) Same as Intussusception.
      [1913 Webster]