the branch of literature comprising works of narrative prose dealing with or offering opinions or conjectures upon facts and reality, including biography, history, and the essay ( opposed to fiction and distinguished from poetry and drama ).
2.
works of this class: She had read all of his novels but none of his nonfiction.
3.
(especially in cataloging books, as in a library or bookstore) all writing or books not fiction, poetry, or drama, including nonfictive narrative prose and reference works; the broadest category of written works.