qui ‧ et ‧ is ‧ m /ˈkwaɪətɪz ə m/ BrE AmE noun [uncountable]
[ Word Family: noun : ↑ quiet , ↑ disquiet , ↑ quietness , ↑ quietism , ↑ quietude ; verb : ↑ quieten , ↑ quiet ; adverb : ↑ quietly ; adjective : ↑ quiet ]
formal when you accept situations and do not try to change them