°(historical astrology alchemy science) The atmospheric substance above the surface of the earth which animals breathe, formerly considered to be a single substance, one of the four basic
elements of ancient philosophy and one of the five basic elements of Eastern traditions.
"The karate instructor said "air is the one thing you can't go five minutes without; when you spar, you have to remember to breathe.""
°To bring (something) into contact with the air, so as to
freshen or
dry it.
°To let fresh air into a room or a building, to
ventilate.
"
It's getting quite stuffy in this room: let's open the windows and air it."