Utterly disgusting. Reserved for situations that call for extreme disgust, like when finding a severed limb inside a cooking appliance.
Dispatcher: "What's the problem there?"
Caller: "I got a human foot."
Dispatcher: "Have a what?"
Caller: "A human left foot in my recently purchased smoker
Dispatcher: "What's your name?"
Caller: "My name's ...
and it's plum nasty, got me grossed out."