abbreviation for 'what the fuck'. Pronounced "Double-you-tee-eff". Could also be abbreviated for Who, where, why, when.
1. Bob: Hey, Joe
Jill: Wtf, no I'm Jill
2. Gorilla: *punches chimpanzee*
Chimpanzee: Wtf was that for?
Person: Wtf!
3. *Billy runs home to find his house got robbed* WTF DID THAT? (Who)
4. *Plane flies off* Fred: *missed plane* WTF did that plane take off without me? (when or why)