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Synonyms

life-threatening

American  
[lahyf-thret-ning, -thret-n-ing] / ˈlaɪfˌθrɛt nɪŋ, -ˌθrɛt n ɪŋ /

adjective

  1. endangering life.

    a life-threatening illness.


Explanation

Something life-threatening is seriously dangerous, and it might even result in death. If someone has a life-threatening illness, it's severe enough that they may need to be hospitalized. You can reassure your mom about the injuries you got when you were hiking up a mountain by saying, "Don't worry, my sprained ankle isn't life-threatening." In other words, it's not going to kill you. Things that are more likely to be life-threatening include cancer, bad head injuries, and run-ins with grizzly bears — they can indeed threaten your life.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

That said, there are cases of endurance athletes drinking excessive fluids, resulting in life-threatening conditions like hyponatremia, when blood sodium levels drop too low.

From The Wall Street Journal Aug. 27, 2026

One million children in Afghanistan are suffering from life-threatening malnutrition in a worsening new crisis hitting the country, the United Nations warned Tuesday.

From Barron's Aug. 25, 2026

Officers treated the victim until they could be taken to a hospital with injuries that police said weren’t life-threatening.

From Los Angeles Times Aug. 24, 2026

A man and woman, both in their 20s, sustained serious but not life-threatening injuries in the collision.

From BBC Aug. 22, 2026

Whenever Keisha showed worrisome symptoms, the Merritts acted as if it was a life-threatening emergency, which made me feel left out.

From "Three Little Words: A Memoir" by Ashley Rhodes-Courter

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