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Can anyone think of any words from backslang to enter the common language apart from "yob"? And is backslang itself still in use anywhere? I know my sister and her school friends used a backslang (I think they called it "Pig Latin")

Pig Latin is alive and well, but I am unaware of any Igpay Atinlay formations which have entered general use except for "ixnay," usually used to discontinue a conversation upon the approach of an authority. I've never heard "yob" in use, but I don't have a lot of exposure to the population groups you would expect to be using the term.

My grandfather taught me Pig Latin. He was born in 1908. I wonder how far back it goes?