Austere; ancient Greek (7)
I believe the answer is:
spartan
I believe this is a double definition.
'austere' is the first definition.
(I know that austere can be written as spartan)
'ancient greek' is the second definition.
(I've seen this before)
(Other definitions for spartan that I've seen before include "Resolute in the face of pain -- austere" , "Very strict - austere" , "Not comfortable" , "Austere, lacking comfort" , "Austere - like Lysander?" .)