n.

1. fear resulting from the awareness of danger;
   dismay, consternation
2. a device that signals the occurrence of some undesirable event;
   warning device, alarm system
3. an automatic signal (usually a sound) warning of danger;
   alert, warning signal, alarum
4. a clock that wakes sleeper at preset time;
   alarm clock

v.

1. fill with apprehension or alarm; cause to be unpleasantly surprised;
   dismay, appal, appall, horrify
   
   • I was horrified at the thought of being late for my interview
   • The news of the executions horrified us
2. warn or arouse to a sense of danger or call to a state of preparedness;
   alert
   
   • The empty house alarmed him
   • We alerted the new neighbors to the high rate of burglaries