Via the null device, I learned something about Polari “(also seen as ‘Palare’), a gay slang language, which has now almost died out. It was more common in the 1960’s when gays had more need of a private slang…(I)n the last few years, more and more people have been finding out about it, and several web sites and magazine articles have been written…. (N)ever clearly defined: an ever-changing collection of slang from various sources including Italian, English (backwards slang, rhyming slang), circus slang, canal-speak, Yiddish and Gypsy languages. It is impossible to tell which slang words are real Polari. The page contains a lexicon of Polari slang of varying authenticity. Here is another lexicon with more source notation. Another essay, in some greater detail, is here at World Wide Words.