Based on a detailed analysis of 11,397 pages from medical manuscripts and early printed books.It includes information on the spelling variants, origins, and meanings of the terms. A wealth of quotations from the texts analysed are provided. Towards the end of each entry, there are references to corresponding entries, if any, in standard historical dictionaries of English (Dictionary of Old English, Middle English Dictionary, The Oxford English Dictionary). If the origin or meaning of the term has been discussed in academic books or articles, references to the latter are also provided.