df
meaning : da fuck

df means almost the same thing as "wtf" but,it's more flexible and,you can use it in more than one way.See example.
Example #1

Cisco:"D00d,that fucking car almost ran me over !"

Mike:"Yeah man,df kind of driving was that ?!"

Example # 2

Cisco:"Your mom was blowin' me real good last night ! XD"

Mike:"df dude !"