When you're hiking for a long period of time, and your butt crack feels dirty and sweaty. So you pull down your pants and underwear, bend over, and let the gust of windblow freely through the crack. It's refreshing and soothing.
There is nothing more rewarding than airingyour ass out after a long and grueling hike.
A type of lying position that's mostly seen done by animals likedogs and cats. It lies on it's back to showing off it's belly, and it's back legs spread are out to a point where you can see the animal's genitals.
"Look how your cat is lying."
"Oh, yeah. She's airing out the valley."