#1 - Cuz / 'Cuz / Becuz
It's a 1337 form of the word because in short.
#2 - Cuz *some-thing-here*
Almost same as above, but used at start of instant messages or chat.
#3 - A man that is a beast
Calling some male person "Kuz" (like Kuz Steven) is the same thing as calling them a beast (Beast Steven) or a freak.
#4 - K.U.Z. or K2UZ
K2UZ meaning 'key to us' or 'key 2 uz'. Not really used.
Geek Kevin: Why you killed Sarah?
1337 Jonny: Kuz sh3 waz a biatxh.
*Super-noob killed TheUltraPro 3 times in a row*.
Mick: cuz... LOL
Greg: yeah... cuz what a pwn.
Lara Nebraska Clint: Steven you're a kuz!
Kuz Steven Clint: What?
Lara N. Clint: YOU FREAKHEAD BEAST!
Kuz Steven Clint: WTF
*Grabs Lara and eats her head*.
Joey: Hey guys, I found a K.U.Z.
Boot & Helyus: Let's open that door..
*Helyus open it and... 'slash!' cuttroath*.
Joey: I found another K2UZ!
Boot: I don't even want to touch it...