A Dictionary of Americanisms, two-volume dictionary of words and expressions that originated in the United States or that were first borrowed into the English language in the United States. Edited by the American scholar Mitford M. Mathews and published in 1951, the dictionary was based on historical principles and was designed to remedy the omissions and deficiencies of The Oxford English Dictionary and the Dictionary of American English on Historical Principles. Unlike the latter, which included many words of British origin, A Dictionary of Americanisms included only words and expressions of American origin. Sources and authorities were cited under each entry, and the pronunciations of many of the words were given.
(Read H.L. Mencken’s 1926 Britannica essay on American English.)