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Synonyms

alarm clock

American  

noun

alarm clocks plural
  1. a clock with a bell or buzzer that can be set to sound at a particular time, as to awaken someone.


alarm clock British  

noun

  1. a clock with a mechanism that sounds at a set time: used esp for waking a person up

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms

Etymology

Origin of alarm clock

First recorded in 1690–1700

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

His alarm clock, a big and bulky machine that’s Bluetooth-connected to the house’s fire alarm, rattles his room until he finally shuts it off.

From Los Angeles Times Jun. 11, 2026

Klugo’s Bluetooth alarm clock isn’t portable, and the hotel alarms ring too softly for him to hear.

From Los Angeles Times Jun. 11, 2026

And then I’ll go “shh” and she’ll stop for a few minutes and the alarm clock goes off and then boom, we launch.

From The Wall Street Journal Jun. 1, 2026

She was joined on the red sofa by her husband Steve, who joked that the "the first thing to go" in their new lives going forward would be the "the alarm clock".

From BBC Apr. 1, 2026

His scuffling woke me as dependably as any alarm clock, my five o’clock possum.

From "The Evolution of Calpurnia Tate" by Jacqueline Kelly

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