Ascetic
Part of speech: adjective
Definition: Of or relating to ascetics; characterized by rigorous self-denial or self-discipline; austere; abstinent; involving a withholding of physical pleasure.
Part of speech: noun
Definition: One who is devoted to the practice of self-denial, either through seclusion or stringent abstinence.
Example sentence: I'm not an ascetic.
Abstainer
Part of speech: noun
Definition: Agent noun of abstain; one who abstains; especially, one who abstains from something they enjoy, such as the use of intoxicating liquors.