The crossword solution for the term 'Abbreviated Mystery Writer' is ANON, which is a four letter word. ANON is an abbreviation for the famous mystery writer Agatha Christie, who is one of the best-selling authors of all time. She wrote over 66 detective novels and 14 short story collections, as well as plays, romances, and poetry. Her works have been adapted into numerous films, television series, and radio programs.