n. & v.
n. 1 a covered walk, often with a wall on one side and a colonnade open to a quadrangle on the other, esp. in a convent, monastery, college, or cathedral. 2 monastic life or seclusion. 3 a convent or monastery.
v.tr. seclude or shut up usu. in a convent or monastery. cloistral adj.
[ ME f. OF cloistre f. L claustrum, clostrum lock, enclosed place f. claudere claus- CLOSE(2) ]