1 - mentally slow

2- Consuming so much alcohol (and / or) drugs that your IQ drops at least 60 points.
Dude - Did you hear that kid? What the fuck was he talking about?

Chick - OMG, I have no idea. His breath smells like dogshit though. Is he fucking retarded or what?

Dude - Nah, he's just slappy mappy.
by IRON SAVAGE December 5, 2011
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