Offering the most accurate and up-to-date coverage of essential, everyday vocabulary and based on evidence from the Oxford English Corpus, a unique databank with hundreds of millions of words of English, the it provides 90,000 words, phrases, and definitions. Definitions are given in a clear, simple style, avoiding technical language, and are easy to understand. There are also hundreds of notes on spelling and grammar. The center section gives guidance on the use of good English, with sections on spelling, punctuation, word classes, and word formation.