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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

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
In many arid areas, dry or shallow creeks can quickly fill up with fast-moving water and become deadly. Hatim Sharif, The Conversation, 5 July 2025 Andy, once a centuries-old immortal who has now lost her healing powers, must race across continents to recover her magic, all the while facing deadly mercenaries and ancient evils. Travis Bean, Forbes.com, 4 July 2025
Adverb
Over the years, anti-affirmative action protests have broken out, some turning deadly – with these groups accusing the government of reverse discrimination, echoing similar controversies in the United States about race-conscious college admissions and job hiring. Jessie Yeung, CNN Money, 16 May 2025 In Oklahoma, people braced for more rain after a deluge turned deadly earlier in the weekend. Emily Mae Czachor, CBS News, 20 Apr. 2025 See All Example Sentences for deadly
Recent Examples of Synonyms for deadly
Adjective
  • Police said less lethal munitions were deployed by federal authorities.
    Jenna Sundel Gabe Whisnant, MSNBC Newsweek, 5 July 2025
  • An attempt to execute an inmate by lethal injection in February 2024 was called off after prison staff failed to properly attach IV lines.
    NBC News, NBC news, 2 July 2025
Adjective
  • The sheer variety of equipment, the pace of change and rising customer demands call for something better: a knowledge capture process that’s baked into the daily workflow.
    Thomas Cottereau, Forbes.com, 9 July 2025
  • Some may prove useful in the long run and others illusory, but for now they are statistically swamped by the sheer amount of renewable power coming online.
    Bill McKibben, New Yorker, 9 July 2025
Adjective
  • The movie follows the adventures of rebellious young boy, Ne Zha, who is feared by the gods having been born to mortal parents with wild, uncontrolled powers.
    Melanie Goodfellow, Deadline, 9 July 2025
  • Populated by roaming blond sausage dogs, ghosts, and several complex mortal humans, Julius Julius satirizes the world of advertising via an ancient company known as Julius Julius, narrated by three different employees in three different eras.
    Hazlitt, Hazlitt, 9 July 2025
Adverb
  • Squishy Pebbles The story of Williams’ new result started with progress on a different question about memory in computation: What problems can be solved with extremely limited space?
    Ben Brubaker, Wired News, 13 July 2025
  • Since its inception, one of the big selling points of the Chromatic has been its extremely durable sapphire display, and interestingly enough, this restock arrives with an additional, cheaper screen option: Gorilla Glass.
    Mitch Wallace, Forbes.com, 13 July 2025
Adjective
  • Priya allegedly injected her business partner with a fatal overdose of sedatives, Joseph said.
    Rhea Mogul, CNN Money, 15 July 2025
  • In the aftermath of Hinton's arrest, members of his family distanced themselves from his actions and instead hired an attorney to conduct a review of the fatal police shooting of his son, Ryan Hinton.
    David Ferrara, The Enquirer, 14 July 2025
Adjective
  • Nonetheless, my hopeful response to my own question is that the transformed form of nature can also be the subject of humanity’s unconditional love.
    PhotoVogue, Vogue, 10 July 2025
  • The unconditional love a therapy dog provides when visiting those battling an illness can be that source of hope.
    Janice Phelan, Kansas City Star, 9 July 2025
Adjective
  • Since the assassination attempt on Trump that left the 50-year-old father dead, the Comperatore family has grappled with lingering and unanswered questions about what led to Comperatore’s death that day.
    Audrey Conklin, FOXNews.com, 12 July 2025
  • Jackson reportedly last checked in with dispatch on June 7 and was eventually found dead by rangers eight days later on June 15 in a camping tent on the Duck Hole trail, which is located in the Adirondack High Peaks, according to the Adirondack Explorer.
    Kimberlee Speakman, People.com, 12 July 2025
Adverb
  • The tape is incredibly sticky and comes with easy-to-follow directions for styling different necklines and silhouettes.
    Malia Griggs, Glamour, 7 July 2025
  • This framing of the three races proved incredibly influential in fantasy fiction, with Tolkien’s work providing a solid foundation for many, many stories to come.
    Dani Di Placido, Forbes.com, 7 July 2025

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Cite this Entry

“Deadly.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/deadly. Accessed 21 Jul. 2025.

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