Lewis & Short

crīmĭnātor, ōris, m. [criminor], an accuser, a calumniator (very rare): meus, Plaut. Bacch. 4, 7, 28: in alios (opp. sui obtegens), Tac. A. 4, 1.
Of the devil, Lact. 2, 8, 6; 6, 4, 2.