Previous posts in this discussion:
PostPolari, A-Slang, Backslang (John Heelan, -UK, 05/18/19 4:42 am)
Gary Moore responded (17 May) about non sequiturs.
Having had to study dead languages like Latin and Greek as a teenager, I am comforted that language creation still thrives, such as reported in Fabulosa! The Story of Polari, Britain's Secret Gay Language, by Paul Baker, 1 Jul 2019.
As teenagers we sometimes hid our conversations from parents and others in authority by using "A-slang," "Backslang" and other disguised languages. Some of my family were Cockneys, born and bred, and automatically used the first words of rhyming slang, e.g. trouble (and strife)=wife, plates of meat=feet, barnet fair=hair, boat race=face, apples and pears=stairs.
A frequently used pejorative borrowed from Yiddish was "bleedin' schnorrer" when somebody was describing somebody else who has upset them in some way.
JE comments: How is it that after a lifetime's fascination with language, I never heard of Polari? It's not just a language of the gay culture, but is shared by other marginalized groups: circus performers, merchant sailors, criminals and prostitutes (per Wikipedia). It borrows heavily from Italian (polari from parlare), Romani, Yiddish, and Cockney rhyming slang. Wikipedia gives a fairly complete glossary:
The Paul Baker book is dated July 2019--I presume that means it's forthcoming? You can pre-order on Amazon.