demonism

1. (uncountable) Belief in, or worship of demons or devils.Examples: "1699, Anthony Ashley-Cooper, 3rd Earl of Shaftesbury, Of Virtue, and the Belief of a Deity, in An Inquiry Concerning Virtue in Two Discourses, London: A. Bell et al., p. 10, […] if he believes more of the prevalency of an ill designing Principle than of a good one, he is then more a Daemonist than he is a Theist, and may be called a Daemonist from the side to which the balance most inclines. ¶ All these sorts both of Daemonism, Polytheism, Atheism, and Theism, may be mixed […]"; "It is very much to be doubted if Mervyn Hogarth had ever in his life given more than a passing thought to any black art or occult science. Certainly he was innocent of prolonged interest in, let alone any practice of, diabolism, witchcraft, demonism, or such cult."uncountable

2. (uncountable, often figurative) The quality of being demonic.Examples: "1915, Henry James, letter to Evan Charteris dated 22 January, 1915 in Percy Lubbock (ed.), The Letters of Henry James, London: Macmillan, Volume 2, p. 453, What a pitiful horror indeed must that Ypres desolation and desecration be—a baseness of demonism."; "What significant illustration of the demonism of the wind does a fallen palm present!"; "Almost alone among contemporary conductors, he avoids the path of demonism; he takes music in his stride and does not press it with febrile intensity."figurativelyoftenuncountable

3. (countable) An act or event attributed to demons or devils; an evil act.Examples: "All that most maddens and torments; all that stirs up the lees of things; all truth with malice in it; all that cracks the sinews and cakes the brain; all the subtle demonisms of life and thought; all evil, to crazy Ahab, were visibly personified, and made practically assailable in Moby Dick."; "So many boys, so many places have disappeared. Blue Gate Fields, scene of many an Asiatic demonism, is gone."countable