Scott-faced is a state of inebriation where the person is groggy, can't stay awake, and is not aware of their own state of being. Similar to a person that has taken too much of an opiate or benzo, or consumed too much alcohol, and refuses to acknowledge this state, preferring to blame it on lack of sleep or sickness. Sometimes referred to as being scootered.
"Dude did you see John yesterday, he was so scott-faced he was drooling all over!"
"I know, he passed out mid-sentence talking to me then acted like nothing happened when I said something to him"