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

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

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

On the bright side, he said, “there’s no problem of having a false alarm or being wrong,” because the predictions won’t affect people on land.

From Los Angeles Times • May 20, 2025

If there is no indication of a false alarm or if a second detector sends a warning, fire alarms are then normally activated throughout the building.

From BBC • Jan. 22, 2025

Dandelion grew nervous and twice gave a false alarm.

From "Watership Down: A Novel" by Richard Adams