perjury (n.)
late 14c., "act of swearing to a statement known to be false," via Anglo-French perjurie (late 13c.) and Old French parjurée "perjury, false witness," both from Latin periurium "a false oath," from periurare "swear falsely," from per- "away, entirely" (see per) + iurare "to swear" (see jury (n.)). Related: Perjurious.