A one time girl who comes about abruptly and wants to hook up with you. You have two options: you can exit the pop up (telling that girl hell no) or you can click on it (getting with the girl) and after leaving on the street like a piece of trash.
Bob: I was on facebook and there was this girl who kept talking to me.

Friend: Dude she is defiantly a pop up
by Adam Secum March 19, 2011
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An advertisement that pops up on your computer screen when you least expect it.
This pop-up stopper is a joke!
by Jesse August 11, 2003
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Serbian power-pop band with a single "Osmeh" that won the first prize on the competition in Serbia among more than 300 other preformers and made a music video which can be watched on youtube.
I totally dislike Pop-ups!
by TrashyBabe. January 11, 2010
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A foldable camper that kicks ass. A place for teens to smoke, drink, and get high off their ass! I definitely wanna road trip that thing.
"Yo, let's go get baked in the popup! Then we can get drunk too!" - EVERYONE
by Nail January 09, 2005
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