dupe¹ / d(y)oōp/ • v. [tr.] deceive; trick: the newspaper was duped into publishing an untrue story.• n. a victim of deception: knowing accomplices or unknowing dupes.DERIVATIVES: dup·a·ble adj.dup·er n.dup·er·y / -pərē/ n.dupe² • v. & n. short for duplicate, esp. in photography.

dupe victim of deception. XVII. — F. dupe, earlier †duppe, said in a text of XV to be a cant term; joc. application of (dial.) dupe hoopoe (of obscure orig.), from the bird's stupid appearance.
Hence vb. XVIII; after F. duper.