A grifter is a con artist: someone who swindles people out of money through fraud.
If there's one type of person you don't want to trust, it's a grifter: someone who cheats others out of money. Grifters are also known as chiselers, defrauders, gougers, scammers, swindlers, and flim-flam men. Selling a bridge and starting a Ponzi scheme are things a grifter might do. The difference between a grifter and a thief is a grifter tricks you out of money through lies, while the thief takes it by force. The end result is the same.