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.
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Recent Examples on the Web: Adjective Even before a deadly virus struck, working at a meatpacking plant could be fatal. USA Today, "Cheap chicken, beef came at a cost. How American meat plants bred coronavirus hot spots.," 22 May 2020 Yet a number of workers have been sent home to be quarantined after potential exposure to the deadly virus in the plant, which some workers say is unsettling. Phoebe Wall Howard, Detroit Free Press, "Assembly worker concerns delay shift start at Ford's Dearborn Truck Plant," 21 May 2020 After all, as Dilley might say, better to infect the people around you with a deadly virus than to risk looking like a dork. Gilbert Garcia, ExpressNews.com, "Garcia: Anti-mask movement won’t let logic get in its way," 20 May 2020 The Vallejo facility marks the latest congregate care setting to be ravaged by the deadly virus. Anna Bauman, SFChronicle.com, "Eleven residents dead in Vallejo nursing home outbreak, more than 130 infected," 18 May 2020 Bodies piled up and fear took over as a deadly virus invaded. Tresa Baldas, Freep.com, "Age of Resistance: How a virus riled up Michigan and spawned a rebellion," 17 May 2020 From a broader social perspective, such a pill would be even more valuable, because any treatment that prevents you from getting sick also prevents you from passing the deadly virus on to others. Justin Wolfers, New York Times, "G.D.P. Doesn’t Credit Social Distancing, but It Should," 14 May 2020 The deadly virus outbreaks at senior communities throughout the country is expected to be front of mind for seniors and their families when deciding whether to move out of their homes. Peter Grant, WSJ, "Senior-Housing Communities Face Higher Vacancy Rates Amid Coronavirus," 12 May 2020 The deadly incident is reminiscent of the 1984 Bhopal disaster, when a gas leak at a pesticide plant killed nearly 4,000 people in the central Indian state of Madhya Pradesh. Vedika Sud, Swati Gupta And Julia Hollingsworth, CNN, "India gas leak prompts investigation and evacuations in Visakhapatnam," 8 May 2020 Recent Examples on the Web: Adverb The racist killings were Germany's third deadly far-right attack in recent months. Fox News, "Thousands mourn victims of Germany shooting massacre with massive march," 24 Feb. 2020 The racist killings were Germany’s third deadly far-right attack in a matter of months. Time, "10,000 Protesters Mourn 9 People Killed by Immigrant-Hating Shooter in Germany," 23 Feb. 2020 During one particularly deadly seven-day period in April, the coronavirus killed more than 50,000 (see chart). The Economist, "Daily chart Covid-19 has become one of the biggest killers of 2020," 1 May 2020 As many have already noted, this macabre roll call reflects the fact that African-Americans are more likely to have preëxisting health conditions that make the coronavirus particularly deadly. Keeanga-yamahtta Taylor, The New Yorker, "The Black Plague," 16 Apr. 2020 Often, the virus doesn't start out feeling deadly, said Katrina Hawkins, an intensive care doctor at George Washington University Hospital in the District of Columbia. Author: Chris Mooney, Sarah Kaplan, Brady Dennis, Anchorage Daily News, "All across the United States, the coronavirus is killing more men than women, data show," 4 Apr. 2020 With a disease that’s highly infectious and can turn deadly, this epidemic violates a sense of control in fundamental ways. Time, "Why People Are Panic Buying as Coronavirus Spreads," 10 Mar. 2020 The company has had several accidents during the past year, although this is the first to turn deadly. Tess Williams, Anchorage Daily News, "Pilot joined Yute Commuter Service a month before crash that left 5 dead in Southwest Alaska," 26 Feb. 2020 Tough, diligent, and deadly serious about the history of art, Krasner might have been the most intelligent of the painters who convinced the world in the late 1940s that New York had displaced Paris as the epicenter of modern art. Jason Farago, New York Times, "Lee Krasner, Hiding in Plain Sight," 19 Aug. 2019

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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Statistics for deadly

Last Updated

25 May 2020

Cite this Entry

“Deadly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deadly. Accessed 5 Jun. 2020.

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More Definitions for deadly

deadly

adjective
How to pronounce deadly (audio)

English Language Learners Definition of deadly

 (Entry 1 of 2)

: causing or able to cause death
: extremely accurate and effective
: extreme or complete

deadly

adverb

English Language Learners Definition of deadly (Entry 2 of 2)

: extremely or completely

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 deadliness (audio) \ noun

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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.

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More from Merriam-Webster on deadly

Thesaurus: All synonyms and antonyms for deadly

Rhyming Dictionary: Words that rhyme with deadly

Spanish Central: Translation of deadly

Nglish: Translation of deadly for Spanish Speakers

Britannica English: Translation of deadly for Arabic Speakers

Comments on deadly

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