But here is the Urban Dictionary entry for whack:
1. whack
1. adjective; appalling in nature, unconventional.
2. verb; to strike one with the hand or fist.
3. verb; to assassinate.
1. yo, that's whack.
2. if your mother heard that she'd whack you upside the head.
3. you want we should whack a dog?
We'll just stay with wack, and know that I'm not lame.
Oh, and it reminds me of Wacky Packs. Anyone here remember those? My brother and I had them stuck all over the place.