alarm clock

noun

Synonyms of alarm clocknext
: a clock that can be set to sound an alarm at a desired time

Examples of alarm clock in a Sentence

She set the alarm clock for six o'clock. The alarm clock went off at six o'clock.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Cell phones have built-in alarm clocks, making the need for a separate wake-up device obsolete. Madeline Buiano, Martha Stewart, 8 Feb. 2026 The circadian rhythm, the body’s natural alarm clock that will suppress melatonin in the morning and increase alertness, is triggered by sunlight. Alexa Mikhail, Flow Space, 4 Feb. 2026 The cameras were allegedly disguised as a phone charger and an alarm clock. Jeff Nguyen, CBS News, 27 Jan. 2026 For the next few days, instead of a blaring alarm clock and taxi cab horns, I am awoken by the deep belly laughter of hippos who live in the lagoon directly outside my door. Condé Nast Traveler, 22 Jan. 2026 See All Example Sentences for alarm clock

Word History

First Known Use

1662, in the meaning defined above

Time Traveler
The first known use of alarm clock was in 1662

Browse Nearby Words

Cite this Entry

“Alarm clock.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alarm%20clock. Accessed 14 Feb. 2026.

Kids Definition

alarm clock

noun
: a clock that can be set to sound an alarm at any desired time

More from Merriam-Webster on alarm clock

Last Updated: - Updated example sentences
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