Platt College On-line Library

Merriam-Webster Online – The online version of Merriam-Webster’s Dictionary and Thesaurus.
OneLook Dictionaries – Searches a number of online dictionaries at one time.
American Heritage Dictionary of the English Language – Online version of the unabridged American Heritage Dictionary.
Wordsmyth English Dictionary-Thesaurus - Use this to search for synonyms, definitions and more.
Lexicool - A directory of over 500 translation dictionaries and glossaries.
YourDictionary.com - A portal for all kinds of dictionaries.
iTools! Language Tools -All in one handy place, general and topical dictionaries, thesauruses, web page translators, homophone finders, rhyming dictionaries, etc. One especially nice feature: click to hear a word pronounced.
Online Etymology Dictionary - Find the origin of everyday words.