Peter Mark —, English physician and lexicographer whose Thesaurus of English Words and Phrases was published in 1852 (5)
I believe the answer is:
roget
(Other definitions for roget that I've seen before include "English physician and thesaurus compiler, d. 1869" , "Thesaurus writer" , "compiler of reference work" , "The man for the synonyms" , "From bookmaker" .)