De-mō'ni-ac or Dē'mo-ni'a-cal1, a.
a. [Lat. dæmoniacus, from dæmon; Fr. démoniaque, Pr. démoniaque, It., Sp., & Pg. demoniaco. See supra.]
Sense 1. Pertaining to, or resembling, demons or evil spirits; horrid. “Thy demoniac holds.” Milton. “Sarcastic, demoniacal laughter.” Thackeray.
Sense 2. Influenced by demons; produced by demons or evil spirits. “Demoniac frenzy.” Milton.