The "Historical Thesaurus of the Oxford English Dictionary" is the first historical thesaurus to be written for any of the world's languages. Conceived and compiled by the English Language Department of the University of Glasgow, and based on the Oxford English Dictionary, it is the result of over 40 years of scholarly labor. The HTOED 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 thesaurus follows a thematic system of classification, with entries arranged in a semantic hierarchy according to their meanings rather than listed alphabetically. This means that, for example, all the verbs meaning 'to eat', and other words connected with eating, can be viewed together. The HTOED also has a unique historical component, and is linked directly to the senses and the dating of words in the Oxford English Dictionary. For each individual entry synonyms are presented in chronological order according to the first recorded date of the word’s use in English, with earliest synonyms first. The HTOED thereby lists obsolete words, and obsolete meanings of current words as well as offering a comprehensive treatment of current English.

The Historical Thesaurus of the Oxford English Dictionary is a fascinating resource for everyone with an interest in the English language and its historical development. It is a perfect complement to the OED itself, allowing the words in the OED to be cross-referenced and viewed in wholly new ways.

*The largest thesaurus resource in the world, covering more than 920,000 words and meanings from Old English to present day, based on the Oxford English Dictionary

*The very first historical thesaurus to be compiled for any of the world's languages

*Synonyms listed with dates of first recorded use in English, in chronological order, with earliest synonyms first

*For obsolete words, the HTOED also includes last recorded use of word

*Comprehensive index enables complete cross-referencing of nearly one million words and meanings

*Includes a free fold-out color chart which shows the top levels of the classification structure