Plural of dupe; people who are easily fooled or deceived, or as a verb, to trick or fool someone.
From French duper, possibly derived from duppe (a hooded pigeon). The word entered English in the late 17th century and has been used both as a noun (a foolish person) and a verb (to deceive).
The fact that we call fooled people 'dupes' shows how animals become symbols in language—calling someone a dupe once meant comparing them to a silly pigeon!
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