1. Pejorative; A regular gym rat who also happens to be a steroid freak. He is very much on the juice to such a degree that he is a pig, hence juicepig.
2. Complimentary; a guy who is so cut and ripped he looks like he could be juicing, even though he's not.
1. Did you see Steve punch the Smith machine? What a fuckin juicepig.
2. You bench how much now Dave? Haha, you juicepig.