Peter Mark Roget, M.D., F.R.S.

Peter Mark Roget FRS (18 January 1779 – 12 September 1869) was a British physician, natural theologian and lexicographer. He is best known for publishing, in 1852, the Thesaurus of English Words and Phrases (Roget's Thesaurus), a classified collection of related words. He is the father of John Lewis Roget and grandfather of Samuel Romilly Roget, both of whom revised and expanded Roget's original work.