(adv)- being intoxicated to the point of potentially or actually vomiting.
Person 1) Man, look at Tom, he's piss-drunk-shitfaced!
Person 2) Aww, he just puked in the fire, we better help him out.
Person 1) Wanna get trashed this weekend?
Person 2) No way, the last time we did, I ended up piss-drunk-shitfaced, we were so loud that we woke up the neighbors.
A phrase or an insult meaning one of three things. One being to actually pee off a cliff, two, being to make a cliff mad, or formally to piss off, but off a cliff.