The adjective austere means something or someone that is very simple and with only the things that are necessary because of limits.

Synonyms are bleak, plain, rough, or severe.

The word origins from Old French austere meaning “strict, severe, harsh, cruel”, directly from Latin austerus meaning “dry, harsh, sour or tart”. It also comes from Greek austeros meaning “bitter, harsh”. It is derived from saus- meaning “dry”. In English, the classical literal sense of “sour, harsh” is rare from the 1540s.

The classroom was plain to the point of austere, with no decorations.

The princess ran away from the castle and chose to live an austere life.

He remained an austere employee and refused to take part in the higher position.