life-threatening

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

ADJECTIVE

very dangerous

Synonyms

STRONGEST

deadly lethal mortal serious severe

WEAK

capital critical hazardous threatening touch and go unsafe

Antonyms

STRONGEST

harmless invigorating

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.

Some prostate tumours do not needed treating immediately and may never be life-threatening, which is part of why widespread screening is not being recommended.

From BBC • Jun. 2, 2026

"If these findings are confirmed in Phase III trials, we may finally be able to offer patients a targeted therapy that halts and potentially reverses liver damage before it progresses to life-threatening stages."

From Science Daily • May 27, 2026

“If I don’t do what’s medically indicated in a potentially life-threatening situation, then I am liable for neglect. Why isn’t this the same thing?”

From Salon • May 27, 2026

The drug could be dispensed only in person by a qualified physician, which protected women with life-threatening ectopic pregnancies.

From The Wall Street Journal • May 17, 2026

Dad was watching baseball, Mom was working on her laptop, and I was experiencing a life-threatening level of boredom.

From "Klawde: Evil Alien Warlord Cat" by Johnny Marciano and Emily Chenoweth