a person who is easily tricked or fooled, or to trick someone
From French 'dupe,' possibly from the hoopoe bird (French 'huppe'), which was considered silly, or from a character in 17th-century French comedy who was always deceived.
Scammers specifically target people they think will be easy 'dupes'—but interestingly, intelligent people can be duped just as easily as anyone else when the scam is clever enough, because duping relies on psychology, not stupidity!
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