Use 'horrify' when someone's response is beyond normal fear, showing intense emotion. The haunted house experience horrified the teenager.
Pro Tip 2/3
Not Physical Harm
'Horrify' refers to emotional impact, not physical harm. Watching the thriller movie horrified her, but she was unharmed.
Pro Tip 3/3
Strong Emphasis
The word 'horrify' adds drama to a sentence; it's much stronger than 'upset' or 'bother'. The extent of pollution in the city horrified the environmentalists.