Commonly used as a
parting statement when saying good bye. People say it and do not ever stop to think about what it really infers when using it. So it is used incorrectly very often. It is actually a put down to the
receiver. It's like saying your behaving odd and or crazy at this particular moment in time. A person in the conversation notes the above and points this out to the receiver by saying it when departing the
conversion and or area. The receiver normally never notices it, so to say “right over their head”. See Have Fun.