A way of referring to sexual intercourse with two (2) female partners, commonly called a threesome. Famously referenced in the CBS comedy "How I Met Your Mother". The first man in a group of male friends to pull off this feat wins the belt as a reward for his skill with women.
Steve: Dude, where were you last night?
Dan: These two girls were hot for me. We all went back to my place and I rode the tricycle with them. I guess I win the belt!
Steve: Dude, I saw those two chicks checking you out. Which one likes you more?
Dan: They're both into me. It's a tricycle!
In conversation it is an expression which follows a particularly good but lighthearted insult in order to emphasize the caliber of the remark. It is similar to the way that a person would use the word burn. Though the phrase itself was first made popular by the Mazda auto commercials, this particular usage was popularized in the popular television show "Scrubs", where it is often accompanied by a short "Zoom, Zoom, Zoom" dance.
Guy 1:Dude, you're pathetic because you've never really satisfied a woman!
Guy 2: Oh really? Well, you might want to check that with YOUR MOM! Ohhhh! Zoom Zoom Zoom !