deadly

adjective
dead·​ly | \ ˈded-lē How to pronounce deadly (audio) \
deadlier; deadliest

Definition of deadly

 (Entry 1 of 2)

1 : likely to cause or capable of producing death deadly poison
2a : aiming to kill or destroy : implacable a deadly enemy
b : highly effective a deadly exposé
c : unerring a deadly marksman
d : marked by determination or extreme seriousness
3a : tending to deprive of force or vitality a deadly habit
b : suggestive of death especially in dullness or lack of animation deadly bores a deadly conversation
4 : very great : extreme

deadly

adverb

Definition of deadly (Entry 2 of 2)

1 archaic : in a manner to cause death : mortally
2 : suggesting death
3 : extremely deadly serious

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Other Words from deadly

Adjective

deadliness noun

Choose the Right Synonym for deadly

Adjective

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

Examples of deadly in a Sentence

Adjective the world's most deadly snake a more deadly form of the disease They launched a deadly attack. Officers are allowed to use deadly force if necessary. She shoots with deadly accuracy. a basketball player with deadly aim A deadly silence followed his question. The two gang leaders are deadly enemies. He spoke with deadly seriousness. Adverb I'm deadly serious about making an offer on the house. See More
Recent Examples on the Web: Adjective Her attorney feared she’d be charged with assault with a deadly weapon, which is punishable by up to four years in prison and a $10,000 fine. Joshua Sharpe, San Francisco Chronicle, 20 May 2022 Los Angeles police initially charged Lee with felony assault with a deadly weapon, but the district attorney's office — which prosecutes felonies — referred the case to the city attorney for possible misdemeanor charges. Tim Stelloh, NBC News, 19 May 2022 The singers are both becoming first-time parents just about a month after Rocky was arrested for assault with a deadly weapon for allegedly firing a handgun at someone following an argument in November 2021. Brendan Morrow, The Week, 19 May 2022 She was then prosecuted in March 2020 on an assault with a deadly weapon charge in California after being released from an Idaho jail for a second time, according to records obtained by Fox News. Fox News, 17 May 2022 As a result, she was charged with burglary of a habitation with the intent to commit aggravated assault with a deadly weapon — family violence. Shafiq Najib, PEOPLE.com, 15 May 2022 Police said that at the time of the shooting, Givens was out on bond from a deadly conduct charge in late January. Chron, 13 May 2022 Givens, who was arrested in the Dallas suburb of Hutchins, was out on bond stemming from a deadly conduct charge in late January, Garcia said. Christine Fernando, USA TODAY, 13 May 2022 At the time of shooting, Givens was free on bond after being arrested in late January on another deadly conduct charge stemming from an incident in the Dallas suburb of Hutchins, Garcia said. Bill Hutchinson, ABC News, 12 May 2022 Recent Examples on the Web: Adverb That may sound like extravagant nonsense, but Milton was deadly serious. John J. Miller, WSJ, 6 May 2022 The Ukrainian president’s evening speeches — now deadly serious — have become routine for many in the country over nearly two months of war with Russia. Washington Post, 21 Apr. 2022 Health experts have warned that the more contagious and possibly more deadly variant sweeping through Britain will probably become the dominant source of infection in the U.S. by March. From Usa Today Network And Wire Reports, USA TODAY, 26 Jan. 2021 The most obvious is that the tails of your skis are waving around behind you, bonking into your friends’ helmets, and making the skis positively deadly in crowded spaces like a gondola line. Bill Gifford, Outside Online, 24 Feb. 2022 Lovell said one team of homicide detectives worked through the weekend, with investigators putting in up to 30 hours straight at some points, to look into both mass shootings and the police deadly shooting. oregonlive, 22 Feb. 2022 The same thing that makes fentanyl so deadly — its potency — allows for its exceedingly compact size. Washington Post, 13 Feb. 2022 The findings from Rhodium are in line with what other researchers have found: that a deadly global pandemic and a massive economic downturn have done little to slow the accumulation of planet-warming gases in the atmosphere. Brady Dennis And Maxine Joselow, Anchorage Daily News, 11 Jan. 2022 Oscar show felt so deadly dull is that nearly all the movie clips were excised from the broadcast. New York Times, 8 Dec. 2021 See More

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

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First Known Use of deadly

Adjective

before the 12th century, in the meaning defined at sense 1

Adverb

before the 12th century, in the meaning defined at sense 1

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Time Traveler for deadly

Time Traveler

The first known use of deadly was before the 12th century

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Dictionary Entries Near deadly

dead loss

deadly

deadly agaric

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Statistics for deadly

Last Updated

24 May 2022

Cite this Entry

“Deadly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deadly. Accessed 26 May. 2022.

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More Definitions for deadly

deadly

adjective
dead·​ly | \ ˈded-lē How to pronounce deadly (audio) \
deadlier; deadliest

Kids Definition of deadly

 (Entry 1 of 2)

1 : causing or capable of causing death deadly poisons
2 : meaning or hoping to kill or destroy deadly enemies
3 : very accurate He shot the arrow with deadly aim.

deadly

adverb

Kids Definition of deadly (Entry 2 of 2)

1 : in a way suggestive of death Her face was deadly pale.
2 : to an extreme degree deadly dull

Choose the Right Synonym for deadly

Adjective

deadly, mortal, and fatal mean causing or capable of causing death. deadly is used of something that is certain or very likely to cause death. The mushroom contains a deadly poison. mortal is used of something that already has caused death or is about to cause death. He received a mortal wound in battle. fatal is used when death is certain to follow. The wounds proved to be fatal.

deadly

adjective
dead·​ly | \ ˈded-lē How to pronounce deadly (audio) \
deadlier; deadliest

Medical Definition of deadly

: likely to cause or capable of causing death a deadly disease a deadly poison a deadly instrument

Other Words from deadly

deadliness \ -​nəs How to pronounce deadly (audio) \ noun

deadly

adjective
dead·​ly
deadlier; deadliest

Legal Definition of deadly

: likely to cause or capable of causing death also : dangerous sense 2

Note: Deadly and dangerous are sometimes used interchangeably, especially in connection with weapons or instruments.

More from Merriam-Webster on deadly

Nglish: Translation of deadly for Spanish Speakers

Britannica English: Translation of deadly for Arabic Speakers

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