The act of pulling your shirt up over your nose to make use of the reserve of air in your shirt that doesn't stink. Usually done when no one else is there to ridicule you for being a wuss.
Dude, someone dropped a deuce in the mensroom that was so bad I had to switch to shirt air.

Hah, Jim is such a girl, someone farts and he instantly switches to shirt air.
by azuremint September 2, 2010
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