One who dupes or deceives someone; a person who tricks or fools others through deception.
From 'dupe' (from French 'dupe,' possibly from 'duppe,' a bird easily trapped) + '-er' (agent noun suffix). The term emerged in English in the 17th century alongside increased use of the verb 'dupe.'
The word 'dupe' possibly comes from a foolish bird in French (the hoopoe, 'huppe'), suggesting that people have been comparing gullible folks to easily-tricked birds for centuries—and a 'douper' is someone who treats people like these silly birds.
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