alarm clock

American  

noun

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

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alarm clock British  

noun

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

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Etymology

Origin of alarm clock

First recorded in 1690–1700

Example Sentences

The 35-year-old in Germantown, Md., wanted a more aggressive alarm clock after sleeping through an important meeting.

From The Wall Street Journal • Mar. 4, 2026

But “somebody who tells me that they need a special alarm clock, to me that’d be a rich area to explore,” said Dr. Rafael Pelayo, a clinical professor at Stanford University.

From The Wall Street Journal • Mar. 4, 2026

The metal ring adds minimal weight when attached and allows the phone to stand in portrait or landscape modes—perfect for reading, watching videos, and propping up the phone as a bedside alarm clock.

From Barron's • Nov. 26, 2025

However analogue clocks will need switching manually, especially important if you are relying on an old-fashioned alarm clock to wake you up.

From BBC • Oct. 11, 2025

Cold is an effective alarm clock, and I was up before the sun.

From "The Marrow Thieves" by Cherie Dimaline

Related Words

• clock radio