The Collaborative International Dictionary of English v.0.48:

Cloister \Clois"ter\, v. t. [imp. & p. p. Cloistered; p. pr. &
   vb. n. Cloistering.]
   To confine in, or as in, a cloister; to seclude from the
   world; to immure.
   [1913 Webster]

         None among them are thought worthy to be styled
         religious persons but those that cloister themselves up
         in a monastery.                          --Sharp.
   [1913 Webster]