means an intense feeling of fear, shock, or disgust — or the thing that causes it, including the film and fiction genre built to provoke it

from From Latin horror, meaning 'a bristling, a shuddering,' from the verb horrere, 'to bristle or stand on end.' The word literally describes what fear does to your body — the hair rising on your arms, the skin prickling into gooseflesh. It came into English through Old French in the medieval period, carrying that same physical shudder: horror was never just a thought, but the body's recoil made into a word.