Acronyms Dictionary

The largest database of acronyms and abbreviations on the web.

Merriam-Webster Online

Offers online dictionary, thesaurus, Spanish-English dictionary, and medical terms.

OneLook Dictionary Search
This site searches for definitions of terms found in 496 general and subject dictionaries.

Roget's Thesaurus (1911)
The 1911 edition of this classic reference work for locating synonyms and antonyms. Presented by the American and French Research on the Treasury of the French Language (ARTFL) Project.

Spanish/English/Spanish Dictionary
Provides translation and definitions for over 25,000 words with 10,000 pronunciation audio clips.

Thesaurus.com

Online version of Roget's II: The New Thesaurus, Third Edition by the editors of the American Heritage Dictionary.

WordNet

Lexical database of English developed by Princeton University's George A. Miller. Nouns, verbs, adjectives, and adverbs are grouped into sets of cognitive synonyms that are linked by conceptual-semantic relations.

Updated 5/16/2008