The Cynic's Word Book is a satirical dictionary written by American journalist and author Ambrose Bierce (1842-ca.1914), a man whose savage wit earned him the nickname "Bitter Bierce". The targets for Bierce's mockery are wide-ranging: from lawyers ("one skilled in circumvention of the law") to the institution of marriage ("a household consisting of a master, a mistress, and two slaves, making in all, two"); from Christians ("one who follows the teachings of Christ in so far as they are not inconsistent with a life of sin), to the very idea of the self ("ALONE, adj. In bad company").

Although it was perhaps the most popular, Bierce's satirical dictionary was certainly not the first. That accolade most probably could go to the 14th-century Persian Nizam-od-Din Obayd-i Zakani. It was in Bierce's time, however, that the idea really took off. In 1911, five years after Bierce's book was first published, Le Dictionnaire des idées reçues (The Dictionary of Received Ideas) by Gustave Flaubert was post-humously released. Compiled from a series of notes written in the 1870s, it isn't clear whether Flaubert ever intended the "dictionary" for publication, but the idea of a spoof encyclopedia had fascinated him all his life.

As for Bierce's effort, it had its seed in a series of newspaper and magazine columns. First appearing in 1881 in the weekly magazine The Wasp, of which he was the editor-in-chief, Bierce worked on the dictionary, which was then called The Devil's Dictionary, between 1881–86, including 88 instalments, each consisting of 15–20 new definitions. When Bierce became an editor of The San Francisco Examiner in 1887, he introduced The Cynic's Dictionary, a continuation on the same theme (with the title changed due to the "the religious scruples" of the paper's owners). The dictionary was first reproduced in book form in 1906 under the title The Cynic's Word Book, and since 1911, expanded editions returning to its original title of The Devil's Dictionary.

Bierce also wrote about his experiences during the Civil War, publishing a collection of 26 short stories entitled Tales of Soldiers and Civilians in 1891. Bierce's death is a mystery: while traveling with rebel troops during the Mexican Revolution in 1913, he disappeared without a trace. His disappearance has become one of the most famous in American literary history.