Synonyms for Ascetic (same or very similar meaning)
WordNet sense 1 (someone who practices self denial as a spiritual discipline):
abstainer
WordNet sense 2 (pertaining to or characteristic of an ascetic or the practice of rigorous self-discipline):
ascetical
WordNet sense 3 (practicing great self-denial):
spartan, austere
WordNet sense 4 (sparing in consumption of especially food and drink):
abstemious
From the ODE community, based on WordNet
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