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... the Historical Thesaurus of the Oxford English Dictionary is the first historical thesaurus to include almost the entire vocabulary of English, from Old English to the present day. Conceived and compiled by the English Language Department of the University of Glasgow, the Historical Thesaurus of the Oxford English Dictionary is a groundbreaking analysis of the historical inventory of English, allowing users to find words connected in meaning throughout the history of the language.
· The largest thesaurus resource in the world, covering more than 920,000 words and meanings based on the Oxford English Dictionary
· The very first historical thesaurus to be compiled for any of the world's languages from medieval times through the present
· Synonyms listed with dates of first recorded use in English, in chronological order, with earliest synonyms first
· For obsolete words, the Thesaurus also includes last recorded use of word
· Made up of two volumes: The main text, comprising numbers sections for semantic categories, and the index, comprising a full A-Z look up of nearly one million lexical items