quacksalver [`kwăk.săl.vur] noun.
1. One who pretends to be an experienced physician and gives medical advice, and so on; a quack.
2. One who fraudulently claims great talents and knowledge; a charlatan; a mountebank.
[Obsolete Dutch kwaksalver: Middle Dutch quacken, to boast, cf. English quack, the sound of a duck, onomatopoetic, & salven fr. West Germanic *salbo-, oily material, from Indo-European root *solpa-, from *selp-, butter or fat]