lethal

play

adjective le·thal \ˈlē-thəl\

Definition of lethal

1a : of, relating to, or causing death death by lethal injectionb : capable of causing death lethal chemicals
2 : gravely damaging or destructive : devastating a lethal attack on his reputation
3 : very potent or effective a lethal fastball; also : having a high alcohol content a lethal rum punch

lethality

play \lē-ˈtha-lə-tē\ noun

lethally

play \ˈlē-thə-lē\ adverb

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Examples of lethal in a Sentence

a potentially lethal dose of a drug
He was sentenced to death by lethal injection.

Recent Examples of lethal from the Web

Christians, meanwhile, accuse Mr El-Rufai of siding with Muslim herders over lethal clashes with farmers in southern Kaduna.

— The Economist, "The lion at bayWould-be successors to the ailing Nigerian president are circling," 20 July 2017
The counselor used physical force to defend himself while an officer fired a less-lethal round at the inmate, Davies said.

— david hernandez, sandiegouniontribune.com, "Inmates attack 3 officers, counselor at Donovan prison," 17 July 2017
Fifty-three Democrats, sensing a lethal threat to their party, fled to Oklahoma, denying Craddick a quorum.

— michelle legro, Longreads, "What’s the Matter With Texas? How Long Do You Have?," 13 July 2017
The telltale blue flash that followed gave Slotin enough radiation to kill him five times over, and the seven observers in the room received doses ranging from nearly lethal to benign.

— patrick malone, Science | AAAS, "A near-disaster at a federal nuclear weapons," 29 June 2017
But the sense of a growing danger of jihadist attacks, even if there aren’t actually more or more lethal attacks, creates the sense that the governments are unable to control the threat on their own.

— david a. graham, The Atlantic, "An Attack From the ISIS Playbook," 19 June 2017
Nearly 1,300 children aged 0 to 17 are killed by gunshots each year in the US, and nearly 5,800 more suffer from non-lethal gunshot wounds, researchers estimate in a study published Monday in Pediatrics.

— beth mole, Ars Technica, "Gunshots are the third leading killer of children in the US," 19 June 2017
Forecasters advised residents to reschedule strenuous activities to early morning or evening and authorities also warned against leaving children or pets in parked cars, which can heat up to lethal levels in just minutes.

— city news service, Ramona Sentinel, "Heat advisory continues; rescuers evacuate hiker from Three Sisters Trail," 18 June 2017
There will be increased demands for reform and review of lethal-use laws, more de-escalation training for police and more awareness of how implicit bias can influence how a police officer reacts and handles a situation.

— rubén rosario, Twin Cities, "Rosario: If abstracts and intangibles were on trial …," 16 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lethal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of lethal

Latin letalis, lethalis, from letum death

NEW! Time Traveler

First Known Use: circa 1604

See Words from the same year

Synonym Discussion of lethal

deadly, mortal, fatal, lethal mean causing or capable of causing death. deadly applies to an established or very likely cause of death. a deadly disease mortal implies that death has occurred or is inevitable. a mortal wound fatal stresses the inevitability of what has in fact resulted in death or destruction. fatal consequences lethal applies to something that is bound to cause death or exists for the destruction of life. lethal gas