a device that makes a loud sound or flashes to warn you or wake you
I set the alarm on my phone for six o'clock.
The store installed a new security alarm after the break-in.
a loud sound, signal, or message that warns people of danger or a problem
The smoke detector suddenly sounded the alarm in the middle of the night.
When the river began to rise, the town siren gave an alarm that everyone could hear.
✦ From Middle French alarme, from Italian all'arme! meaning “to arms!”. Originally a cry to call soldiers to their weapons, it later came to mean any warning of danger.
a sudden feeling of fear or worry that something bad may happen
He gazed at the empty campsite with alarm, afraid his friends were lost.
The sudden crash filled her with alarm.
to make someone suddenly feel worried, afraid, or anxious
The loud bang alarmed the passengers on the train.
News of the approaching storm alarmed coastal residents.
