AS you say, polari is almost entirely made up of loan words - including backslang. e.g. lyrig - girly, as in, " that lyrig has real bona lallies. Shame she's a chavering donna!"

There's lots of Italian loans [polari derives from It "parlare = to speak] and quite a few Romany i.e. gypsy, words (rather than Romanian, strictly speaking, although I guess there is some connection there.) A very flamboyant and colourful language.

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