Mr. Hemingway (6)
I believe the answer is:
ernest
(Other definitions for ernest that I've seen before include "Boy's name (the important one!)" , "Name beloved of Gwen Fairfax (Wilde)" , "First name of . . . . . . Hemingway, American novelist" , "- Hemingway, US author" , "American writer . . . . . . Hemingway" .)