An annoying twat who sits behind you just watching you browse the internet or my documents. Anything. Anything they can get their watchful eyes onto. This could be you brother, your best friend or a stranger at the libary.
Person 1: What's Tim doing.

Person 2: oh he's just Back-seat Browsing on Percy over there.

Person1: Does Percy know?

Person 2: Hell no man, otherwise he would be so pissed.
by The hidden undermass June 23, 2011
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