ascetic has definitions from the field of religion
1
[ adjective ] practicing great self-denial

Examples

"Be systematically ascetic...do...something for no other reason than that you would rather not do it"- William James "a desert nomad's austere life" "a spartan diet" "a spartan existence"

Related terms

abstemious

2
[ adjective ] pertaining to or characteristic of an ascetic or the practice of rigorous self-discipline

Synonyms

ascetical

Examples

"ascetic practices"

Related terms

abstainer abstainer

3
[ noun ] (religion) practices self denial as spiritual discipline

Synonyms

abstainer

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