Dictionary.com
Thesaurus.com
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.

Keep Reading on Vocabulary.com

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:

Bristol Myers Squibb told regulators, researchers and patient-advocacy groups in early June that it had paused closely watched drug research because of life-threatening side effects.

From The Wall Street Journal Sep. 3, 2026

However, court documents said his condition was not "life-threatening" and added he would be able to access care in the UK.

From BBC Aug. 30, 2026

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

After recovering from the life-threatening illness, Hilton made the decision to relocate his family to Miami in June.

From Los Angeles Times Aug. 26, 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

Vocabulary.com logo
by dictionary.com

Join 12,000,000 vocabulary learners

Start learning new words today on VocabTrainer.
You'll remember them forever.

Start training