Dictionaries
Many of the general reference sites also include dictionaries in their databases.
Oxford Reference Online Premium
Oxford Reference Online Premium is an online collection of authoritative language and subject reference works from one of the world's biggest reference publishers. The Core Collection (ORO) is a fully-indexed, cross-searchable database. The Premium Collection (OROP) provides added functionality and more detailed information across a broad subject range from titles in the world-renowned Oxford Companions Series. Bilingual dictionaries are available as well as English, including: French, Spanish, German, Irish, Italian, and Welsh.
Concise Oxford English Dictionary
Based on the authority of the Oxford English Corpus and the ongoing research of Oxford Dictionaries, the eleventh edition of the Concise Oxford English Dictionary offers rich vocabulary coverage, with full treatment of World English, rare, historical, and archaic terms, as well as scientific and technical vocabulary.
This new edition is completely up to date with 5,000 new words and senses. It features 2,200 uniquely Canadian words and senses, 350 usage notes, 7,000 idiomatic expressions, 5,500 biographical entries, and over 5,600 place names.
The Merriam-Webster Online Dictionary is based on the print version of Merriam-Webster's Collegiate® Dictionary, Eleventh Edition. The online dictionary includes the main A-Z listing of the Collegiate Dictionary, as well as the Abbreviations, Foreign Words and Phrases, Biographical Names, and Geographical Names sections of that book.
Not only a standard dictionary, Your Dictionary.com contains specialty dictionaries for a number of professions and interest and dictionaries in over 300 languages. To find translations and languages other than English, click the “Other Dictionaries” tab and then “Language Dictionaries and Translation Websites.”