FRESHNESS
air something out
to freshen up something by placing it in the open air; to freshen a room by letting air move through it.It's so stale in here. Mary, please open a window and air this place out.Please take this pillow outside and air it out.I'll have to air out the car. Someone has been smoking in it.
(as) fresh as a daisy
very fresh; fresh and alert.The morning dew was as fresh as a daisy.Sally was fresh as a daisy and cheerful as could be.
breath of fresh air
air that is not (figuratively) contaminated with unpleasant people or situations.You people are disgusting. I have to get out of here and get a breath of fresh air.I believe I'll go get a breath of fresh air. The intellectual atmosphere in here is stifling.