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mid-12c. "grant, commission" (recorded earlier in Old English, but as a Latin word), from Old French privilege "right, priority, privilege" (12c.) and directly from Latin privilegium "law applying to one person, bill of law in favor of or against an individual," later "privilege," from privus "individual" (see private (adj.)) + lex (genitive legis) "law" (see legal (adj.)). Meaning "advantage granted" is from mid-14c. in English.