a one

[Mnemon]

Hello.
Does the usage ring any bells for you? Do you consider it old-hat?
The screenshot was taken from the book Oxford Dictionary of Slang written by John Ayto.

 

[SoothingDave]

No, this is not used today.

 

[probus]

It survives as part of "great one". For example: Joe was a great one for practical jokes.

 

[emsr2d2]

It's used in BrE. Admittedly, the simple "Oooh, you are a one!" would generally be said in a rather silly voice!

 

[jutfrank]

It sounds a bit old-fashioned to me. Like something out of a 1970s sitcom.