What is an synonym for the word appalled?

Here are some synonyms for "appalled," depending on the specific nuance you're looking for:

General disgust or horror:

* Horrified

* Shocked

* Dismayed

* Aghast

* Stunned

* Disgusted

* Repulsed

* Sickened

* Outraged

Strong disapproval or anger:

* Indignant

* Furious

* Enraged

Fear or trepidation:

* Terrified

* Scared

* Frightened

Other possibilities:

* Astonished

* Amazed (in the sense of being negatively surprised)

* Bewildered

The best synonym for "appalled" will depend on the specific context of your sentence.