When you are doing
something that is not the socially accepted
norm and it often makes no reasonable sense to other
people why you are behaving in such a manner.
Don is bolding whenever he smokes a cigarette because he unconsciously (or consciously) smokes it as fast as possible and ends up with a
cherry the size of your thumb.
When Don arrives at a bring and braai with no food or drink, and proceeds to eat a second helping before
people that brought food have
even had one helping, we say to ourselves "Oh yes. Don is bolding again"