Merriam-Webster Dictionary from Mirriam Webster.
Merriam-Webster Thesaurus from Mirriam Webster.

Bartleby.com

Cambridge International Dictionaries Online
Search Cambridge's Dictionary of American English, International Dictionary of English, International Dictionary of Phrasal Verbs, and International Dictionary of Idioms.

Dictionary of Measures, Units and Conversions
A summary of most of the units of measurements to be found in use around the world today and a few of historical interest, together with appropriate conversion tables.

Dictionary of Phrase and Fable
from 1870. Searchable and browseable.

Encyclopedia of Western Signs and Ideograms
Search by word or by graphic.

Everybody's Law Dictionary
Plain English definitions for legal terms. Search by term or subject.

Latin-English Dictionary
Perseus Project, Tufts University. Also available: English-Latin Dictionary

Oxford English Dictionary**

Medical Dictionary- MedlinePlus

OneLook Dictionaries
OneLook allows for easy, quick word searches in more than 600 online dictionaries, including general, legal, and foreign dictionaries.

Roget's Thesaurus 1911 edition

Webopedia.com
A dictionary of computer and Internet technology terms

Your Dictionary.com
Over 800 dictionaries in 160 languages including WWWebster.

** Available to Chapman community only.