World Book Dictionary
 The World Book Dictionary is a two-volume English dictionary published as a supplement to the World Book Encyclopedia. It was originally published in 1963 under the editorship of Clarence Barnhart who wrote definitions for the Thorndike-Barnhart graded dictionary series for children based on the educational works of Edward Thorndike whom Clarence Barnhart had known and worked with decades before. In some editions it was called the World Book Encyclopedia Dictionary.