A monster is any of a large number of legendary creatures which usually appear in mythology, legend, or horror fiction. The word originates from the ancient Latin monstrum, meaning "omen", from the root of monere ("to warn") and also meaning "prodigy" or "miracle".
The term "monster" refers to a being that is a gross exception to the norms of some ecosystem. Usually characterized by an ability to destroy human life or humanity, more than an example of "survival of the fittest", natural law, or innate evil. A person referred to as a monster is taken as exceptionally evil, grotesque, unreasonably strict and uncaring, sociopathic, and/or sadistic. The word monster connotes something wrong/evil; e.g.: a monstrous being is: very morally objectionable, physically or psychologically hideous, or a biological sport (a distinct sense of the word), i.e a freak of nature.