O is for "The Devil's Dictionary" (No. 191 in a series)

The Devil's Dictionary is a satirical dictionary written by Ambrose Bierce (1842-c.1914, caricatured above by David Levine). Bierce was an American author who began the book as a newspaper serial. First published in 1906 as The Cynic's Word Book, it was retitled in 1911, using the name we know it by today, which is the title that Bierce preferred. Some of the definitions have not aged all that well, but many have.

OPTIMIST, n. A proponent of the doctrine that black is white.