I
J
- Jabolo - Greeting, used mainly in the southwest (http://www.ee.ed.ac.uk/~ee3kv/jabolo.html)
- jemandem einen blasen - to blow someone
K
- kacken - to shite
- Kennsch de Wehn? (Wehn intressiert's?) - Who the hell cares (lit. Do you know someone (who cares))
- kiffen - to get stoned
- Kippe, die - cigarette
- Kiste, die - rack (sexual)
- Kitzler - clit
- Klampfe - Guitar
- klatschen - (lit. to clap) racist slur for beating
- Klo, das - the loo 1
- Klugscheißer, der - smartass 1
- Knallen - to bang (sexual)
- kotzen - to puke
- krank - (lit. sick) context can indicate a woman is 'on the rag'
- kübeln - (lit. "to bucket") puke
1 Directly taken from http://notam.uio.no/~hcholm/altlang/ht/German.html