What is a Thesaurus?
A thesaurus is a dictionary of synonyms and homonyms (for which see above). alphaDictionary has integrated the best English dictionary, the American Heritage. Dictionary of the English Language, 4th edition, with Houghton Mifflin's New Roget's Thesaurus, 2nd Edition so that you can search both at the same time. In the thesaurus, synonyms are stacked on top of each other while antonyms are ordered vertically, back to back, to help you quickly identify them.