From Wiktionary, the free dictionary
real jam (uncountable)
- (UK, slang) Anything exceptionally good.
- That's the real jam!
- George Augustus Sala, The Story of Jack the Painter, in 1863, Tales and Essays (volume 3, page 10)
- It's real jam, that little pictur his [sic]. I wouldn't mind springin' the price to a century. There! Shall I send my boy round to tell him so?
1877, Punch, page 134:It was real jam to see little NORRIS, who was out for the first time, in a horrid state about his four greys.
- John Camden Hotten (1873) The Slang Dictionary
