austere
adjective
Definition
Stern in manner; without excess, unadorned
Synonyms
uncompromising, strict, solemn
Antonyms
luxurious, comfortable, lush
Two Sentences
1.) Etiquette schools are very austere and do not tolerate any sloppy behavior.
2.) The mother told her son to keep his room neat and austere when the guests would arrive at their home.
Word Tutor - Austere