A euphemism for "getting high", aka smoking marijuana. As defined by the comedian Throwing Toasters, referring to The Pheromones singing a cover of the song "High" by Feeder. It was a very funny night!
Where did Michael go? Oh, he's out hot air ballooning with his friends... Don't wait up 'cause he won't be home today.
by izzygalvez January 29, 2009
Farting into the fourskin of a semi erect penis
Brian's fourskin inflated as bob passed wind down his limp shaft. Hot air ballooning
by Sheppytrain June 16, 2013