The Oxford English Dictionary (OED) is widely regarded as the accepted authority on the English language. It is an unsurpassed guide to the meaning, history, and usage of 500,000 words and phrases past and present, from across the English-speaking world.
The OED online consists of the the complete text of the OED's twenty-volume second edition and three-volume Additions Series, along with draft material from the current OED project, representing the latest progress towards a completely revised and updated third edition. Updates are made continually.