ahdictionary.com

The much-anticipated Fifth Edition of The American Heritage Dictionary of the English Language is the premier resource about words for people who seek to know more and find fresh perspectives. Exhaustively researched and thoroughly revised, the Fifth Edition contains 10,000 new words and senses, over 4,000 dazzling new full-color images, and authoritative, up-to-date guidance on usage from the celebrated American Heritage Usage Panel.