Polari is an eclectic mix of slang, dialects and foreign words, and original words and phrases, woven into English language grammar and syntax. Even today, you have used Polari if you've ever had a few bevvies at the pub, zhooshed up your bijou flat, or said something is a bit naff.
Before homosexuality was decriminalised, Polari allowed gay people to speak openly and identify themselves as gay without attracting unwanted interest or the attention of undercover charpering omis (policemen). Unless you were in the know, you would only partially understand what was being said and hear nothing incriminating.
How gay men used to speak: a short film in Polari | Brian Fairbairn and Karl Eccleston | 24 Jun 2015 | 6m 17s
Learn these shady Polari phrases during quarantine, You cackling Alice! | Hornet | Daniel Villarreal | 3 Apr 2020
Polari: The code language gay men used to survive | BBC Culture | 13 February 2018
Polari | The One BBC: One Show 17 Jan 2010 | 4m 00s
Stuart Feather and Bette Bourne talk about Polari | Re-Dock | 28 May 2014 | 4m 40s
Bona Eke: Song in Polari | artdecoandy | 7 Dec 2014 | 5m 03s
Polari | Wikipedia
Polari: Word List | Chris Denning
Polari, a vibrant language born out of prejudice | The Guardian | 24 May 2010
The secret language of polari | Merseyside Maritime Museum
Polari Magazine | Polari Magazine