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Fairly common in UK English, particularly in London which has long-term Jewish community.

It's slangy and self-consciously borrowed, like 'schlep' or 'schmuck' in New York English.

I was born and raised in the UK and have never heard of it. No Jewish friends or family though.

Very much a London-centric word, originally. And it seems like people of a certain age heard it all over the country on telly.