spartan

Dictionary definition · Spartan

of or relating to or characteristic of Sparta or its people
resolute in the face of pain or danger or adversity"spartan courage"
unsparing and uncompromising in discipline or judgment"a parent severe to the pitch of hostility"
practicing great self-denial"Be systematically ascetic … do … something for no other reason than that you would rather not do it"

Source: Open English WordNet (CC BY 4.0).