Longman Dictionary of Contemporary English by Longman
Based on the 100-million word British National Corpus and the Longman Corpus Network, this dictionary explores a vivid and exciting area of English - spoken English. It also pinpoints the language patterns and grammar unique to spoken English. The 2000-word Longman Defining Vocabulary is made up of words students already know, and the dictionary's definitions have been written using this familiar set of core words.