life-threatening

adjective

life-threat·​en·​ing ˈlīf-ˌthre-tᵊn-iŋ How to pronounce life-threatening (audio)
-ˌthret-niŋ
: capable of causing death : potentially fatal
a life-threatening disease/condition
The injuries are serious but not life-threatening.

Examples of life-threatening in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Cardiac Risk in the Young (CRY) conducts screenings on the general population for those between 14 and 35 years old and found that one in every 300 people has a life-threatening heart defect. — Jordan Campbell, New York Times, 6 Sep. 2026 Swells from Lowell are expected to cause life-threatening surf and rip current conditions in portions of the Islands during the next several days. — Doyle Rice, USA Today, 5 Sep. 2026 She was taken to a hospital with non-life-threatening injuries, police said. — Marlene Lenthang, NBC news, 5 Sep. 2026 After Barrett was located, responding officers found Walsh upstairs in a bathtub with non-life-threatening knife wounds that were believed to be self-inflicted. — Angel Saunders, PEOPLE, 5 Sep. 2026 See All Example Sentences for life-threatening

Word History

First Known Use

1759, in the meaning defined above

Time Traveler
The first known use of life-threatening was in 1759

Browse Nearby Words

life table
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lifetime
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Cite this Entry

“Life-threatening.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/life-threatening. Accessed 6 Sep. 2026.

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Medical Definition

life-threatening

adjective
life-threat·​en·​ing ˈlīf-ˌthret-ən-iŋ How to pronounce life-threatening (audio)
: capable of causing death : potentially fatal
life-threatening injuries
a life-threatening allergic reaction
life-threatening arrhythmia
Last Updated: - Updated example sentences
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