Lewis & Short

plăgĭārĭus, ii, m. [plagium].

  1. I. A torturer, oppressor, plunderer (class.): Licinium plagiarium cum suo pullo milvino tributa exigere, Cic. Q. Fr. 1, 2, 2, § 6: inter avaros, circumscriptores, latrones, plagiarios unum esse cui noceri non possit, Sen. Tranq. 8, 4.
  2. II. Esp., a man-stealer, kidnapper (post-Aug.), Dig. 21, 1, 17; 47, 2, 49; 53; 48, 15, 1; Callistr. Ib. 6; Vulg. 1 Tim. 1, 10.
    1. B. Transf., a literary thief, plagiarist (one who pretends to be the author of another’s book), Mart. 1, 53, 9.