AIR

noun

1. The substance constituting earth's atmosphere, particularly:
2. (usually with the) The apparently open space above the ground which this substance fills, formerly thought to be limited by the firmament but now considered to be surrounded by the near vacuum of outer space.
3. A breeze; a gentle wind.

verb

1. To bring (something) into contact with the air, so as to freshen or dry it.
2. To let fresh air into a room or a building, to ventilate.
3. To discuss varying viewpoints on a given topic.