The Historical Thesaurus of English is the first historical thesaurus ever produced for any language, containing almost every word in English from Old English to the present day. Of major interest to historians, philologists, linguists, and the general reader, the Thesaurus is an unrivalled resource for the historical study of the language. It is based on a comprehensive analysis of English as found in the Oxford English Dictionary (OED) and A Thesaurus of Old English (for words restricted to the Old English period of c700-1150 AD). All these words and their dates of recorded use are displayed within a detailed semantic framework, offering a fascinating picture of the development of the vocabulary of English from its origins in early medieval times to the present.

Such an arrangement casts new light on the relationship between the things and ideas people talk about and the words they use and have used in the past, as well as on the words themselves. By browsing through the Thesaurus, or examining one of its categories in detail, the reader will encounter a huge variety of intriguing words from many different sources, ranging from the rare or obsolete to those which have been in daily use for hundreds of years or introduced recently.

These pages give you comprehensive information about the Thesaurus, including its principles of categorization, sources, history, and more. From the menu at the left, you can choose any of our information pages to read more; we recommend you begin with the key documents in larger font (such as the Guide to the Thesaurus and the Story of the Thesaurus), and then progress to the further details found under each of these as your interests allow.

Key Information

The Historical Thesaurus is organized into three major sections, reflecting the main activities and preoccupations of users of the language: the External World, the Mental World, and the Social World. These in turn are divided into 377 major categories, such as Food, Thought, or War. Further categories and subcategories follow, moving from the most general ideas to the most specific. The semantic categories and subcategories are headed by phrases which define them and link to preceding sections. In the example below, the headings and numbering show that the teeth, at the seventh level of the semantic hierarchy, are part of the mouth, which is classified as a digestive organ within the higher category of digestive and excretive organs, which in turn are a part of the body:

Within these categories, words which share a high proportion of their meaning are organized by part of speech and presented in chronologically ordered lists. Each word is accompanied by its dates of recorded use and by any relevant restrictive labels given in the OED, such as ‘poetic’ (poet.) or ‘Australian’ (Austral.). We provide some figures regarding the size of the Thesaurus database and depth of its categorization on our figures page.

The Historical Thesaurus is the product of over fifty years of dedicated scholarship by many hands at the University of Glasgow and elsewhere. The editors would like to thank everyone who has contributed: university staff in Britain and abroad, research assistants, postgraduate students, computing staff, and data entry personnel. It is impossible to mention everyone by name, but the Acknowledgements page sets out those who have had a major involvement. Maintaining a project of this size and scope is no easy matter, and we would also like to thank those who have funded the project and had faith in its work. Special thanks are due to the University of Glasgow as the main host of the project over the years, alongside King’s College London for the Old English materials, and other financial support is listed on the Funders page.