1. Someone who lives in a "world" where videogames are the most important thing ever. Xbox games specifically. This person is so involved in videogames that they forget the rules of basic hygiene. This person usually wears the same set of clothing for weeks at a time without feeling the need to wash it. The stench of this person can get so bad that it engulfs the entire room, and remains lingering even after the person leaves.

2. Someone who pretends to like box, but in fact hates it. This person would usually prefer a granddaddy penis in their mouth.
1. Dude, you've been playing COD all day. Take a shower and quit being a jeffbox.

2. Dude, that kid's such a jeffbox! He just told me he'd totally bang your sister, but then he was checking out your Dad's ass! Fucking GROSS.
by BaconFlavoredCoke February 25, 2009
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