Grifter
noun

- a person who tricks people into giving them money, etc.

Oxford Learner's Dictionary

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A “grifter” is a petty criminal who tricks unsuspecting people, often by exploiting human weaknesses and vulnerabilities, especially greed and loneliness, usually to extract money.

Grifters work so convincing that the police frequently have a hard time convincing the victims that they have been the victim of a crime..

The categories of “con artist,” “swindler” and “grifter” are not precise and overlap, but generally a “grifter” tries to forge a personal relationship with the victim and then extracts loans and other expensive favors.

“Grifter” is of American origin, dating back to the early 20th century, but appears to be based on the slightly older slang term “grafter,” also meaning “swindler,” “con man” or simply “thief.”  

Some authorities believe that “grifter” is actually a combination of “grafter” and “drifter,” reflecting the rootless lives of such people.

“Grafter,” in turn, comes from the noun “graft,” meaning, as the Oxford English Dictionary defines it, “the obtaining of profit or advantage by dishonest or shady means; the means by which such gains are made, especially bribery, blackmail, or the abuse of a position of power or influence.” 

The roots of “graft” in this sense are uncertain, but some etymologists believe it's based on an old British slang use of “graft” to mean “dig” or “work,” based on the same root that gave us “grave” (old High German grab meaning grave or tomb).

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SYNONYMS

con artist, swindler, con man, confidence man, defrauder, scammer, cheat, cheater, chiseler, deceiver, card sharp, gouger sharpie, welsher, beguiler, trickster