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1520s, "to persuade a vassal, etc., to desert his allegiance or service," from Latin seducere "lead away, lead astray," from se- "aside, away" (see secret (n.)) + ducere "to lead" (see duke (n.)). Sexual sense, now the prevailing one, is attested from 1550s and apparently was not in Latin. Originally "entice (a woman) to a surrender of chastity." Related: Seduced; seducing.
Replaced Middle English seduisen (late 15c.), from Middle French séduire "seduce," from Old French suduire "to corrupt, seduce," from Latin subducere "draw away, withdraw, remove," from sub- "from under, further" (see sub-) + ducere "to lead" (see duke).