Merriam-Webster's Dictionary

A handy, reliable, and authoritative dictionary of words most frequently used in English. More than 75,000 definitions, 2,000 new word entries, and more than 150 illustrations. Expanded special features include a Handbook of Style, Basic English Grammar, Irregular English Verbs and a Guide to Common Verb Collocations (both essential for ESL), and a new Overview of the Internet.