The spot of light created by sunlight reflecting off a watch or a mobile object. First known usage in the 1970s in the Hexham area; now known to have spread to Oxfordshire and Bermuda.
What happens to one when riding in a fast car with a friend and you get so scared you squeeze the apolstery from the seat between your butt cheeks thus having apolstery crack as the end result.
He was driving so fast that the girl in the back seat clenched her butt cheekstogether so hard she got apolstery crack.