Millionaire Jay of fiction (6)

I believe the answer is:

gatsby

(Other definitions for gatsby that I've seen before include "Novel millionaire" , "F Scott Fitgerald wrote 'The Great ......'" , "F Scott Fitzgerald wrote 'The Great . . .'" , "Fitzgerald's tycoon" , "Fitzgerald's great hero" .)

I've seen this clue in The Wall Street Journal.

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