Historical Thesaurus of the OED

The Historical Thesaurus of the OED is a unique resource charting the semantic development of the huge and varied vocabulary of English. It is the first comprehensive historical thesaurus ever produced for any language, and contains almost every word in English from Old English to the present day.

With 800,000 words and meanings, in 235,000 entry categories, the thesaurus offers a complete sense inventory for English—from Old English to the present day, based on the second edition of the OED and A Thesaurus of Old English.

Now part of the OED Online, the Historical Thesaurus allows readers to discover synonyms for individual words in the OED (and then trace their development over time), and to chart the linguistic progress of a chosen object, concept, or expression, with links to the OED definition of each new word.

The Historical Thesaurus of the OED was conceived and compiled by the English Language Department of the University of Glasgow. The following guides, written by members of its editorial team, explain different aspects of the thesaurus.