Bogey is a word with a host of meanings: an evil spirit; something persistently annoying; a score of one-over-par on a golf hole; an unidentified or enemy aircraft; a detective; or something disgusting in, or that's come out of, a nose.
I'm afraid it's the last meaning that's especially interesting to me. When I went to Ireland a couple of years ago to talk at the Children's Literature Festival it was the one word I used that people didn't understand.
In one place, the wonderfully named Sallynoggin, the word I should have used was mer-mer (sorry, I don't know how to spell that, but that was how you said it). A dozen miles up the road, however, no one had ever heard of a mer-mer - or a bogey, for that matter.
There it was, rather delightfully, a snotter!
Word to use today: bogey. The word seems to be related to the Scots word bogill and the Welsh bygel, meaning scarecrow, and perhaps to the Middle Welsh bwg, which means ghost, and the Cornish buccaboo, the devil.