The American Heritage Dictionary of the English Language

"Thoroughly revised, the fifth edition contains 10,000 new words and senses, over 4,000 ... new full-color images, and authoritaive, up-to-date guidance on usage from the ... American Heritage Usage Panel ... Thousands of definitions have been revised in rapidly changing fields such as astronomy and biology, geographical entries and maps have been completely updated, and the dictionary's signature feature notes on word history, synonymy, and language variation have been enhanced and improved"--Dust jacket flap.