[noun] [U]Quiet means the state of being silent.Let's have some quiet!I go camping for some peace and quiet (= absence of activity and excitement).(informal disapproving) If you do something on the quiet, you do it secretly or in such a way that most other people do not notice it.He was accepting bribes on the quiet.
QUIET
Meaning of QUIET in English
Cambridge English vocab. Кембриджский английский словарь. 2012