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

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.

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

Isaac Manuel Orozco, 39, was convicted by a Kern County jury of aggravated mayhem, attempted aggravated mayhem, burglary and assault with a deadly weapon, according to online jail records. Vandana Ravikumar, USA TODAY, "A California man was found guilty of aggravated mayhem this week. He ripped out eyeball of his wife's lover," 18 July 2019 Williams was arrested April 29 on charges of burglary with assault or battery and aggravated assault with a deadly weapon, online records from Palm Beach County in Florida show. Steve Almasy And Madeline Holcombe, CNN, "WNBA suspends LA Sparks guard Riquna Williams for 10 games after domestic violence allegation," 17 July 2019 And the following day, Portwood was further charged with domestic battery, criminal recklessness committed with a deadly weapon and domestic battery committed in the presence of a child less than 16 years old, according to Page Six. Jodi Guglielmi, PEOPLE.com, "Teen Mom OG's Amber Portwood Posts Cryptic Message About Cheating After Arrest," 17 July 2019 Butler previously has been convicted of drug possession, assault with a deadly weapon, kidnapping and robbery. Elise Schmelzer, The Denver Post, "Prosecutors say a Civic Center Park drug dealer killed 3 homeless people over a $200 debt. His attorneys say the murders were more likely tied to “Gutter Punk” gang.," 17 July 2019 Howard has a prior conviction in the 1980s of aggravated assault with a deadly weapon. Houston Chronicle, "Houston man tells police he 'lost his cool' in fiancee's fatal stabbing," 16 July 2019 He was convicted of assault with a deadly weapon in that case, which occurred in Guerneville on Jan. 27, 2009. Matthias Gafni, SFChronicle.com, "Sonoma County man gets 3 life sentences for Jenner beach slayings of young couple," 15 July 2019 Garefos, 37, of Fort Worth has been indicted on one count of aggravated assault with a deadly weapon. Emma Ruby, Dallas News, "Uber driver unhappy with company's response to Haltom City attack that left her bloody, shaken," 15 July 2019 Friday, July 5 Male, 41, arrested on suspicion of assault with a deadly weapon not a firearm, 1000 block Main Street. Ramona Sentinel, "Sheriff’s Reports: June 27 to July 7," 10 July 2019

Recent Examples on the Web: Adverb

If Bourbon virus were to establish itself there in humans too, the chances go up that more cases, like Wilson’s, will turn deadly. Megan Molteni, WIRED, "The Meat-Allergy Tick Also Carries a Mystery Killer Virus," 8 July 2019 All too often, these types of incidents can turn deadly. Kim Chatelain, nola.com, "Road rage in Slidell leads to shooting: police," 27 June 2019 This can turn deadly fast if heat waves strike and last for several days. Ivana Kottasová, CNN, "Europe prepares for scorching heat wave with public cooling rooms, mist showers and health warnings," 25 June 2019 While June has been particularly deadly, the first half of this year saw fewer homicides in the city than any year since 2012. Cameron Knight, Cincinnati.com, "June has been the deadliest month in Cincinnati since 2010," 13 June 2019 Other cases detail how similar callousness or poor judgment can turn deadly: In Knox County, Tennessee, an inmate who tried to kill himself with a razor six months earlier was given another one when readmitted on theft charges. Sharon Cohen, The Denver Post, "AP Investigation: Many U.S. jails fail to stop inmate suicides," 18 June 2019 Demonstrations on the Gaza-Israel border have picked up in the past two weeks, sometimes turning deadly as protesters have clashed with Israel’s security forces. Dov Lieber, WSJ, "Six Palestinians Die in Clashes at Gaza-Israel Border," 28 Sep. 2018 Schlenk used his next two picks with that in mind: Maryland’s Kevin Huerter (deadly from the outside) and Villanova forward Omari Spellman, who plays a creative offensive game and can hit the three-pointer. Bruce Jenkins, SFChronicle.com, "As the Warriors go their way, the big men multiply," 23 June 2018 OLYMPIA — Community advocates, law-enforcement groups and state lawmakers are vowing to quickly approve the compromise legislation that was thrown out by the courts earlier this year to change Washington’s police deadly-use-of-force law. Joseph O’sullivan, The Seattle Times, "Community advocates, law enforcement groups call for Legislature to pass compromise bill on police deadly force," 3 Dec. 2018

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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Statistics for deadly

Last Updated

21 Jul 2019

Look-up Popularity

Time Traveler for deadly

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

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More Definitions for deadly

deadly

adjective

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

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

Rhyming Dictionary: Words that rhyme with deadly

Thesaurus: All synonyms and antonyms for 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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