Today’s word is quiet, because sometimes you just want things quiet.
Quiet showed up in the early fourteenth century as a noun and the late fourteenth century as an adjective and a verb. It comes from the Old French quiete/quiet, rest or tranquility, and classical Latin quies, rest and its verb form quietare, which means lull or make quiet. It can be traced even further back to the Proto Indo European kweie, to rest or be quiet, and the origin word for while. Not making that up. Quiet and while are (distantly) related.
Sources
University of Texas at San Antonio’s page on Proto Indo European language
