pox doctor
/ˈpɒks ˌdɒktə/noun
A doctor specializing in the treatment of venereal disease. got up like a pox doctor's clerk and variants: dressed smartly but in bad taste; overdressed. Also figurative rare before 20th cent.
Origin
Late 17th century; earliest use found in William Petyt (?1641–1707), lawyer and political propagandist. From pox + doctor.