Noah Webster's Dictionary 1. (a.) Pertaining to, or characteristic of, a demon or evil spirit; devilish; as, a demoniac being; demoniacal practices. 2. (a.) Influenced or produced by a demon or evil spirit; as, demoniac or demoniacal power. Int. Standard Bible Encyclopedia POSSESSION, DEMONIACAL de-mo-ni'-a-kal (Matthew 4:24; Matthew 8:16, etc.). See DEMON, DEMONIAC, DEMONOLOGY.

Multi-Version Concordance Demoniacal (1 Occurrence) James 3:15 This wisdom descendeth not from above, but is earthly, sensual, demoniacal. (WBS)