To have a subconscious, random, vocal outburst which is both completely irrelevant and out of context. Usually brought on by the excessive use of alcohol/drugs and tiredness.
Person B: " Is everyone ok here in the front room?"
Person A: "I can’t believe this part of the M23 is so busy"
Person B: What?
Person A: What?
Person B: "You’re not on the M25, you’re in my living room. Did you just popout?"
Person A: Yeah I think so"