Who uses it: Writers and literary critics
What it means: Literally, "a novel with a key," a fictional narrative based on actual events and real people
How you can use it: When discussing the works of Neil Simon, Woody Allen, Jack Kerouac, and many others.
As a rule, I have very little patience with autobiographical novels. While it's true that we all star in our own life stories, the adjunct to that is that the rest of the planet is just our stage set and everyone we meet is just a supporting character -- and that idea horrifies me. I see a lot of manuscripts of first novels, and far too many of them are narcissistic fairy tales or revenge fantasies. (Not that I have anything against a good revenge fantasy.)
It's my main problem with the later works of Neil Simon, including the play that Gaslight's doing now. My theory is that fame and grief have made his world smaller and smaller and smaller, and the plays reflect that.
This is one of those late-night conversations more suitable for a writer's conference: whose frame of reference should you use, if not your own? But the writer's privilege is to make the world as big as she wants it to be, and to keep the frame tightly around one's own self, with the microscope focused inward, seems to be missing an opportunity.