Joseph Emerson Worcester (24 August 1784-27 October 1865) was Noah Webster's foremost rival in the field of lexicography. After Webster's death Worcester carried on the rivalry with the firm of G. & C. Merriam for some twenty years, during which many of Worcester's ideas were adapted to the scheme of the Webster dictionaries. His most important contribution to the development of the dictionary was his introduction of the practice of carefully discriminating among words closely related in meaning. In contrast to Webster, who could not resist the temptation to reform language according to his own inspirations, Worcester saw his role as modern lexicographers do, to dispassionately and systematically gather, sift, and weigh the best available evidence from actual usage. As such, Worcester continued to influence lexicographical practice well into the twentieth century. A native of Bedford, New Hampshire, and educated at Yale, he settled in Cambridge and first applied himself to...