of or pertaining to monasteries

a monastic library.

of, pertaining to, or characteristic of monks or nuns, their manner of life, or their religious obligations

monastic vows.

of, pertaining to, or characteristic of a secluded, dedicated, or austere manner of living.

a member of a monastic community or order, esp. a monk.

adjective

ascetic , austere , celibate , contemplative , monkish , oblate , reclusive , secluded , solitary