I had the same initial reaction to the thread title, but figured it out when I read the OP.
As it happens, I’ve actually written this short story. Sadly unpublished. (This was many years ago when I actually tried to get some short fiction published. I never got anything more than a perfunctory rejection letter).
It’s a slang term that was current and widely used during noir’s heyday. In context, it’s exactly the correct word to use in describing the trope.