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Synonyms for Alarm (same or very similar meaning)

WordNet sense 1 (fear resulting from the awareness of danger):
consternation, dismay

WordNet sense 2 (an automatic signal (usually a sound) warning of danger):
alert, alarum, warning signal

WordNet sense 3 (a clock that wakes sleeper at preset time):
alarm clock

WordNet sense 4 (a device that signals the occurrence of some undesirable event):
alarm system, warning device

WordNet sense 5 (fill with apprehension or alarm; cause to be unpleasantly surprised):
appal, appall, horrify

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