On a multiple day psychedelic bender. Usually happens at music festivals and hippie gatherings.
A: Hey man, you didn't get on the bus yet, did you? We still need to get our tent up.
Bar-hopping without a plan, in search of something (or someone) better. Most often used derogatively, as this kind of night rarely turns out well.
We've already been to two bars. If you're going to be on the bus all night then I'm going home.
A subtle way to indicate a lesbian!
Ray : that girls hot!
Brian: your wasting your time mate she's on the bus!
Term used to describe the last day at work before your vacation. You are at work physically, but not mentally.
Boss: "Hey, get back to work, you haven't done crap all day!"
Employee: "Sorry, I'm on the bus, going on vacation tomorrow."