The subject of this chapter is the contribution of early modern law lexicons to the English language. The author explores the influence on the English vernacular of the works of lawyer-lexicographers such as John Ratsell and John Cowell, who integrated Civil and Common Law in his 1607 work, The Interpreter. The linguistic backdrop for this is one where English was only gradually displacing Law French and Latin. The author shows the importance of patronage in the emergence of these new lexicographical works and how they were aimed at the education of a new legal profession ‘conversant in the languages of European business and diplomacy’. These works extended beyond their own register, expanding the vocabulary of the general language and, in the case of The Interpreter with its use of quotations and references to other books, ultimately inspired the innovative structure of the major works of English lexicography that followed.