ASCETICAL
ascetic, ascetical, austere, spartan
(adjective) practicing great self-denial; “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”
ascetic, ascetical
(adjective) pertaining to or characteristic of an ascetic or the practice of rigorous self-discipline; “ascetic practices”
Source: WordNet® 3.1
Adjective
ascetical (comparative more ascetical, superlative most ascetical)
ascetic
Source: Wiktionary