Jezebel is an example of an eponym, a person whose name has evolved into a common noun or verb. In addition to eponyms, the English language is peppered with historical allusions that have become disassociated from their original context. How many people realize that the phrase "mad as a hatter" refers to the dementia suffered by Victorian hatmakers, who were poisoned by the mercury used in their craft? This work is the first reference book in English specifically devoted to uncovering the origins of these unique words and phrases. It provides a concise definition of the contemporary meaning of each term, followed by a detailed explanation of the events that gave rise to it. The 750 entries encompass allusions and eponyms from all eras of history.