deadly 1 of 2

Definition of deadlynext
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deadly

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adverb

Synonym Chooser

How does the adjective deadly differ from other similar words?

Some common synonyms of deadly are fatal, lethal, and mortal. While all these words mean "causing or capable of causing death," deadly applies to an established or very likely cause of death.

a deadly disease

When would fatal be a good substitute for deadly?

In some situations, the words fatal and deadly are roughly equivalent. However, fatal stresses the inevitability of what has in fact resulted in death or destruction.

fatal consequences

When is lethal a more appropriate choice than deadly?

While in some cases nearly identical to deadly, lethal applies to something that is bound to cause death or exists for the destruction of life.

lethal gas

When could mortal be used to replace deadly?

The synonyms mortal and deadly are sometimes interchangeable, but mortal implies that death has occurred or is inevitable.

a mortal wound

How does the adjective deadly differ from other similar words?

Some common synonyms of deadly are fatal, lethal, and mortal. While all these words mean "causing or capable of causing death," deadly applies to an established or very likely cause of death.

a deadly disease

When would fatal be a good substitute for deadly?

In some situations, the words fatal and deadly are roughly equivalent. However, fatal stresses the inevitability of what has in fact resulted in death or destruction.

fatal consequences

When is lethal a more appropriate choice than deadly?

While in some cases nearly identical to deadly, lethal applies to something that is bound to cause death or exists for the destruction of life.

lethal gas

When could mortal be used to replace deadly?

The synonyms mortal and deadly are sometimes interchangeable, but mortal implies that death has occurred or is inevitable.

a mortal wound

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of deadly
Adjective
The attack in Shreveport was among the deadliest mass shootings since January 2024. Makenzie Boucher, USA Today, 27 Apr. 2026 Runaway Bay is in recovery mode after a deadly tornado hit the edges of its southwestern, western, and northern corners, Mayor Herman White said. Marvin Hurst, CBS News, 27 Apr. 2026
Adverb
The weekslong deadly and escalating conflict in the Middle East has amplified those fears. Alicia Wallace, CNN Money, 31 Mar. 2026 This involves a trip behind the Iron Curtain, where cultural misunderstandings can quickly turn deadly serious. Entertainment Weekly, 10 Mar. 2026 See All Example Sentences for deadly
Recent Examples of Synonyms for deadly
Adjective
  • Little in the past acknowledged his preference for lethal injection between the two methods, sharing concerns over the impacts on corrections officials from participating in a firing squad execution.
    Kevin Fixler April 29, Idaho Statesman, 29 Apr. 2026
  • But as the data shows, violence is largely concentrated among a small number of individuals and increasingly smaller, yet no less violent and lethal, groups of street gangs and crews.
    Andrew S. Boutros, Chicago Tribune, 29 Apr. 2026
Adjective
  • But the 6-foot-5 Dennis-Sutton’s potential and sheer agility are off the charts, at his size.
    Luca Evans, Denver Post, 25 Apr. 2026
  • The format has its limitations, though — the most obvious for fans with an inclination to ship is the sheer inability to develop romantic relationships over the course of a season.
    Payton Turkeltaub, Variety, 25 Apr. 2026
Adjective
  • But James has been much more mortal in the two games since, and the Lakers have lost both.
    Los Angeles Times, Los Angeles Times, 30 Apr. 2026
  • Yet there’s wisdom amid the silliness, as the story gently makes a case for the necessity of grief, mindfulness and mortal awareness, even in a life otherwise unburdened by adult human responsibility.
    Guy Lodge, Variety, 27 Apr. 2026
Adverb
  • These special releases can be extremely valuable, especially if only a small batch is issued.
    Nina Derwin, Martha Stewart, 30 Apr. 2026
  • The innermost region of any solar system, closest to the parent star, will be extremely hot and subject to large amounts of radiation.
    Big Think, Big Think, 30 Apr. 2026
Adjective
  • Homicide detectives are investigating the fatal shootings of three adults in Baldwin Park last week — two of whom were a married couple, officials said, who were being mourned by their college-age children.
    Karen Garcia, Los Angeles Times, 28 Apr. 2026
  • Police have arrested a man on murder and firearm charges in connection with a fatal shooting in Stratford earlier this month.
    Justin Muszynski, Hartford Courant, 28 Apr. 2026
Adjective
  • The series poignantly addresses the complexities of teenage struggles, particularly through Justin’s undiagnosed ADHD and Keisha’s experience of trauma, emphasizing the importance of unconditional support and the intersection of mental health with race and class in today’s world.
    Brande Victorian, HollywoodReporter, 23 Apr. 2026
  • The limited goal of bringing the regime to heel expanded immediately into its unconditional surrender and potential annihilation.
    Fintan O’Toole, The New York Review of Books, 9 Apr. 2026
Adjective
  • Suspect One was dead and Suspect Two was on the run.
    Saïd Sayrafiezadeh, New Yorker, 26 Apr. 2026
  • That includes clearing dead or dying vegetation within 100 feet of all structures, landscaping with fire-resistant plans and non-flammable ground cover, and disposing of landscaping debris in other ways.
    City News Service, San Diego Union-Tribune, 25 Apr. 2026
Adverb
  • And yes, in 2026, rage coming from either side of the aisle is an incredibly powerful tool for marketing.
    Alison Foreman, IndieWire, 28 Apr. 2026
  • But there’s something incredibly unnatural about the fast attention of the internet.
    Charlie Harding, Vulture, 28 Apr. 2026

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Cite this Entry

“Deadly.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/deadly. Accessed 1 May. 2026.

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