• Noun: a mixture of gases (especially oxygen) required for breathing; the stuff that the wind consists of; examples: "air pollution", "a smell of chemicals in the air", "open a window and let in some air", "I need some fresh air"
• Noun: travel via aircraft; examples: "air travel involves too much waiting in airports", "if you've time to spare go by air"
• Noun: the region above the ground; examples: "her hand stopped in mid air", "he threw the ball into the air"
• Noun: medium for radio and television broadcasting; examples: "the program was on the air from 9 til midnight", "the president used the airwaves to take his message to the people"
• Noun: a slight wind (usually refreshing); examples: "the breeze was cooled by the lake", "as he waited he could feel the air on his neck"
• Noun: a distinctive but intangible quality surrounding a person or thing; examples: "an air of mystery", "the house had a neglected air", "an atmosphere of defeat pervaded the candidate's headquarters", "the place had an aura of romance"
• Noun: the mass of air surrounding the Earth; examples: "there was great heat as the comet entered the atmosphere", "it was exposed to the air"
• Noun: a succession of notes forming a distinctive sequence; example: "she was humming an air from Beethoven"
• Noun: once thought to be one of four elements composing the universe (Empedocles)
• Verb: expose to fresh air; example: "aerate your old sneakers"
• Verb: be broadcast; example: "This show will air Saturdays at 2 P.M."
• Verb: broadcast over the airwaves, as in radio or television; example: "We cannot air this X-rated song"
• Verb: make public; example: "She aired her opinions on welfare"
• Verb: expose to warm or heated air, so as to dry; example: "Air linen"
• Verb: expose to cool or cold air so as to cool or freshen; examples: "air the old winter clothes", "air out the smoke-filled rooms"
• Adj: relating to or characteristic of or occurring in the air; examples: "air war", "air safety", "air travel"
As to the effect of the wave on the air, we will suppose the water to be quite flat and the air motionless, a heavy undulation comes on the scene, it has to pass, so it pushes the air up with its face, letting it fall again as its back glides onwards.
If we were driving pure hydrogen automobiles, that automobile would actually help clean up the air because the air coming out of the exhaust would be cleaner than the air going into the engine intake.
Air travel survived decades of terrorism, including attacks which resulted in the deaths of everyone on the plane. It survived 9/11. It'll survive the next successful attack. The only real worry is that we'll scare ourselves into making air travel so onerous that we won't fly anymore.
The other thing that happened was my last military assignment - this was in the air force; I had enlisted in order to avoid being drafted as a private, and of course I only practiced medicine or psychiatry in the air force so I was never in any kind of violent combat.