From Longman Dictionary of Contemporary Englishmountebankmoun‧te‧bank /ˈmaʊntɪbæŋk/ noun [countable] literary ALDISHONESTa dishonest person who tricks and deceives people
Examples from the Corpus
mountebank• Politically, Mr Ashdown is a mountebank, not a moralist.• He hated being the object of public attention and ridicule like some fairground mountebank.• Are you allowing yourselves to be fooled by this mountebank, this harlequin?• She was to marry this mountebank, this hypocritical toad of a Sir Thomas.Origin mountebank (1500-1600) Italian montimbanco, from monta in banco “get on the bench”; because people selling things to the public stood on a raised surface 