mountebank
/ˈmaʊntəˌbæŋk/
noun
- A person who pretends to have skills or knowledge they do not have, especially in order to trick people; a fraud or charlatan.
- Politicians sometimes act like mountebanks, promising things they can never deliver.
- The self-proclaimed doctor turned out to be a mountebank selling fake cures.
- Don't trust that mountebank; he's just trying to sell you a worthless investment.