Pronunciation: (non-fik'shun),[key] —n. 1. 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. (esp. 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.