'appal' definitions:

Strike with disgust or revulsion; "The scandalous behavior of this married woman shocked her friends" [syn: shock, offend, scandalize, scandalise, appal, appall, outrage]

Fill with apprehension or alarm; cause to be unpleasantly surprised; "I was horrified at the thought of being late for my interview"; "The news of the executions horrified us" [syn: dismay, alarm, appal, appall, horrify]