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noun \ə-ˈlärm\

Simple Definition of alarm

  • : a device that makes a loud sound as a warning or signal

  • : a feeling of fear caused by a sudden sense of danger

  • : a warning of danger

Full Definition of alarm

  1. 1 usually alarum archaic :  a call to arms <the angry trumpet sounds alarum — Shakespeare>

  2. 2 :  a signal (as a loud noise or flashing light) that warns or alerts; also :  a device that signals <set the alarm to wake me at seven>

  3. 3 :  sudden sharp apprehension and fear resulting from the perception of imminent danger

  4. 4 :  a warning notice

Examples of alarm

  1. The alarm went off when he opened the door.

  2. The whole town heard the alarm.

  3. She set the alarm for six o'clock.

  4. The alarm went off at six o'clock.

  5. The rumors caused widespread alarm and concern.

  6. His parents have expressed alarm about his safety.

  7. The new developments are being viewed with alarm.

  8. She looked around in alarm when she heard the noise.

  9. The dog's barking gave the alarm and the intruders were caught.

  10. A passerby saw the intruders and raised the alarm.

Variants of alarm

also ala·rum play \ə-ˈlär-əm also -ˈler-; -ˈla-rəm\

Origin of alarm

Middle English alarme, alarom, from Middle French alarme, from Old Italian all'arme, literally, to the arms

First Known Use: 14th century

Synonym Discussion of alarm

fear, dread, fright, alarm, panic, terror, trepidation mean painful agitation in the presence or anticipation of danger. fear is the most general term and implies anxiety and usually loss of courage <fear of the unknown>. dread usually adds the idea of intense reluctance to face or meet a person or situation and suggests aversion as well as anxiety <faced the meeting with dread>. fright implies the shock of sudden, startling fear <fright at being awakened suddenly>. alarm suggests a sudden and intense awareness of immediate danger <view the situation with alarm>. panic implies unreasoning and overmastering fear causing hysterical activity <the news caused widespread panic>. terror implies the most extreme degree of fear <immobilized with terror>. trepidation adds to dread the implications of timidity, trembling, and hesitation <raised the subject with trepidation>.




Simple Definition of alarm

  • : to cause (someone) to feel a sense of danger : to worry or frighten (someone)

Full Definition of alarm

  1. transitive verb
  2. 1 :  to strike with fear

  3. 2 :  disturb, excite

  4. 3 :  to give warning to

  5. 4 :  to equip with an alarm

alarm·ing·lyplay \-ˈlär-miŋ-lē\ adverb

Examples of alarm

  1. I didn't mean to alarm you.

  2. The rapid spread of the disease has alarmed many people.


First Known Use of alarm


Variants of alarm

also alarum

Seen and Heard

What made you want to look up alarm? Please tell us where you read or heard it (including the quote, if possible).


February 7, 2016

a slight offense

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