Wikia

Monster (also referred to as a monster film', creature feature or monster movie) is a name commonly given to films that center around the struggle between human beings and one or more monsters. While there is no specific academic genre classification of that name, the term is usually applied to films sometimes labeled as horror, fantasy, or science fiction films.

These films involve fictional creatures, but in most cases they are over-sized monsters, despite its beginnings with adaptations of horror folklore and literature. In Japanese cinema, such monsters are referred to as Kaiju.

Typically, monsters in films differ from more traditional antagonists in that many exist due to circumstances beyond their control; their actions not entirely based on choice, potentially making them objects of empathy to film viewers.