—n.
1 a warning of danger etc. (gave the alarm).
2 a a warning sound or device (the burglar alarm was set off accidentally). b = alarm clock.
3 frightened expectation of danger or difficulty (were filled with alarm).
—v.tr.
1 frighten or disturb.
2 arouse to a sense of danger.
Phrases and idioms:
alarm clock a clock with a device that can be made to sound at the time set in advance.
Etymology: ME f. OF alarme f. It. allarme f. all' arme! to arms
Useful english dictionary. 2012.