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1. Struck with fear, dread, or consternation
   - aghast, dismayed, shocked

1. Strike with disgust or revulsion
   "The scandalous behaviour of this married woman appalled her friends"
   - shock, offend, scandalize, scandalise [Brit], appall [US], outrage
    
2. Fill with apprehension or alarm; cause to be unpleasantly surprised
   "I was appalled at the thought of being late for my interview"
   - dismay, alarm, appall [US], horrify

See also: afraid, 'fraid [non-standard]

Type of: affright, churn up, disgust, fright, frighten, nauseate, revolt, scare, sicken