warning

American  

[wawr-ning] / ˈwɔr nɪŋ /

noun

1. the act or utterance of one who warns or the existence, appearance, sound, etc., of a thing that warns.

2. something that serves to warn, give notice, or caution.

   We fired a warning at the intruders.

   Synonyms:

   presage, augury, portent, sign, omen, advice, admonition, caution

3. Meteorology. an announcement from the U.S. National Weather Service alerting the public that a storm or other weather-related hazard is imminent and that immediate steps should be taken to protect lives and property.

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adjective

1. serving to warn, advise, caution.

   a warning bell.

warning British  

/ ˈwɔːnɪŋ /

noun

1. a hint, intimation, threat, etc, of harm or danger

2. advice to beware or desist

3. an archaic word for notice

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adjective

1. (prenominal) intended or serving to warn

   a warning look

2. (of the coloration of certain distasteful or poisonous animals) having conspicuous markings, which predators recognize and learn to avoid; aposematic

Other Word Forms

• warningly
  adverb

Etymology

Origin of warning

First recorded before 900; Middle English (noun); Old English war(e)nung “precaution”; see warn, -ing ¹, -ing ²

Explanation

A warning is a caution against something dangerous. When there's a shark warning at the beach, the lifeguards will order everyone out of the water. When you receive a warning, you get an official advance notice of some impending problem. A crow might caw loudly as a warning when it sees a cat, and a traffic cop might give a first-time speeder a warning instead of an expensive ticket. You can also use warning as an adjective: "The warning light came on in her car as it started to overheat."

Example Sentences

Thomas Friedman, a prominent New York Times opinion columnist, authored a piece this week titled “Anthropic’s Restraint Is a Terrifying Warning Sign.”

From MarketWatch • Apr. 11, 2026

Warning: It doesn’t matter where you are in the general crowd, you need to be aware of mosh pits breaking out around you at any point.

From Los Angeles Times • Apr. 9, 2026

Warning signs continue to mount for business development companies, as years of accumulated stress begin to show up in their portfolios of loans to midmarket borrowers.

From The Wall Street Journal • Mar. 30, 2026

Warning times ranged from just a few minutes to as much as eight hours before an eruption began.

From Science Daily • Mar. 15, 2026

He, an alleged psychologist, noticed not one of the Ten Warning Signs of Nervous Collapse or whatever it was that he was educated to see, and qualified to teach.

From "The Secret History" by Donna Tartt

Related Words

• admonition
• advice
• alarm
• alert
• caution
• example
• guidance
• hint
• indication
• information
• lesson
• notification
• prediction
• recommendation
• sign
• signal
• suggestion
• threat
• word