The term 'hostile spirit' can be summarized as an ANIMUS, which is a Latin word meaning 'MIND' or 'SOUL'. It is often used to refer to a deep-seated feeling of animosity or resentment towards someone or something. In psychology, it is used to describe a person's unconscious desire to harm or destroy another person or thing. In literature, it is often used to describe a character's inner struggle between good and evil. In mythology, it is used to describe a supernatural being that is hostile towards humans.