Source : Webster's Revised Unabridged Dictionary (1913)

Cloistral \Clois"tral\, a.
   Of, pertaining to, or confined in, a cloister; recluse.
   [Written also {cloisteral}.]

         Best become a cloistral exercise.        --Daniel.

Source : WordNet®

cloistral
     adj : of communal life sequestered from the world under religious
           vows [syn: {cloistered}, {conventual}, {monastic}, {monastical}]