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internĕcīnus or internĕcīvus, a, um, adj. [internecio], deadly, murderous, destructive (class.): bellum, Cic. Phil. 14, 3, 7; Liv. 9, 25 fin.; 22, 58, 3: odia, Just. 6, 6: internecini actio, for poisoning, Cod. Th. 9, 1, 14: internecini judicium, of one who has committed perjury, acc. to Isid. Orig. 5, 26.
Adv.: internĕcīnē, with utter destruction: cuncta disperdere, Amm. 27, 9, 6.