–noun

1. a person who dedicates his or her life to a pursuit of contemplative ideals and practices extreme self-denial or self-mortification for religious reasons.
   
2. a person who leads an austerely simple life, esp. one who abstains from the normal pleasures of life or denies himself or herself material satisfaction
   
3. (in the early Christian church) a monk; hermit.

1. pertaining to asceticism.
2. rigorously abstinent; austere: an ascetic existence.
3. exceedingly strict or severe in religious exercises or self-mortification.