false alarm

American  

noun

1. a false report of a fire in progress to a fire department.

2. something that excites unfounded alarm or expectation.

   Rumors of an impending transit strike proved to be a false alarm.

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false alarm British  

noun

1. a needless alarm given in error or with intent to deceive

2. an occasion on which danger is perceived but fails to materialize

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false alarm Idioms  

1. A warning signal that is groundless, made either by mistake or as a deliberate deception. For example, The rumor that we were all going to get fired was just a false alarm, or Setting off a false alarm is a criminal offense. This expression, first recorded in 1579, today is often used for a report of a nonexistent fire.

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Etymology

Origin of false alarm

First recorded in 1570–80

Example Sentences

Doubts about the current bull market have started to creep in following Friday’s tech stock wipeout, but this wouldn’t be the first false alarm.

From The Wall Street Journal • Jun. 8, 2026

Chronic pain, however, continues even after the injury has healed, creating a kind of false alarm that can last for weeks, months, or years.

From Science Daily • Apr. 27, 2026

After another false alarm that the case had been found, Rosie's husband Chris says he began emailing Ryanair "twice a week for months" in the hope of an update.

From BBC • Mar. 11, 2026

I see some information about cops scrambling, but an editor says it’s a false alarm and not to worry about it.

From Slate • Jun. 17, 2025

I laughed with them, at Teacher Li who had not made the message clear, at my own fears, at the whole false alarm.

From "Red Scarf Girl: A Memoir of the Cultural Revolution" by Ji-li Jiang