To horrify means to fill someone with horror, shock, or intense disgust. When something horrifies you, it affects you deeply, making you feel sick to your stomach or frozen with shock at how awful it is.

A gruesome scene in a movie might horrify viewers. Learning about a terrible disaster can horrify people. You might be horrified to discover that someone threw trash in a beautiful river, or horrified when you see how badly your little brother scratched your favorite book. Teachers are often horrified when they catch students treating each other cruelly.

The word suggests a strong emotional response that combines fear, shock, and revulsion. If your friend is merely startled by a spider, she's not horrified. But if she discovers that someone has been secretly reading her diary, she might be genuinely horrified by that violation of privacy.

Notice that horrify is stronger than words like “upset” or “disturb.” When something horrifies you, it shakes you deeply. You might say “I was horrified to learn...” when describing your reaction to truly disturbing news. The feeling of being horrified can combine moral outrage with visceral disgust: it's not just wrong, it's deeply, shockingly wrong.