Bottom scratcher is not a term familiar in the U.S.

But then again, the name on the cereal box in the U.S is "Rice Crispies" whereas in Austalia it is Rice Bubble, and we don't have Vegemite. We call them vans, in the UK they might be called a lory, and in Australia I think the term is canby. We call it an electrical exstension cord versus "flex" in the UK, and the fish we call a "grouper" is called a "groper" in Australia, whereas a groper in the U.S. is some man or woman who likes to cop a feel off strangers, but I will guess "cop a feel" is strictly an American term.