lethal

adjective

ˈlē-thəl How to pronounce lethal (audio)
Definition of lethalnext
as in deadly
likely to cause or capable of causing death we were lucky that the snake's venom wasn't lethal, and our friend turned out to be all right

Synonyms & Similar Words

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Antonyms & Near Antonyms

Synonym Chooser

How does the adjective lethal differ from other similar words?

Some common synonyms of lethal are deadly, fatal, and mortal. While all these words mean "causing or capable of causing death," lethal applies to something that is bound to cause death or exists for the destruction of life.

lethal gas

When is deadly a more appropriate choice than lethal?

The words deadly and lethal can be used in similar contexts, but deadly applies to an established or very likely cause of death.

a deadly disease

When could fatal be used to replace lethal?

Although the words fatal and lethal have much in common, fatal stresses the inevitability of what has in fact resulted in death or destruction.

fatal consequences

When might mortal be a better fit than lethal?

While in some cases nearly identical to lethal, 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 lethal That trash will get broken down, or someone will attempt to make some use out of it—to extract some profit from it—and that’s an extremely dangerous and often lethal process where all sorts of contaminants and forever chemicals enter local ecosystems. —Brianne Kane, Scientific American, 11 July 2025 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 Their bites deliver one of the most lethal types of venom in North America. —Brandi D. Addison, Austin American Statesman, 2 July 2025 See All Example Sentences for lethal
Recent Examples of Synonyms for lethal
  1. deadly
  2. fatal
  3. poisonous
Adjective
  • The clinic helps prevent the spread of this deadly disease in the U.S.
    — Nicole Villalpando, Austin American Statesman, 31 July 2025
  • The man faces five criminal charges including unlawful possession of a firearm by a serious violent felon and criminal recklessness with a deadly weapon.
    — Jordan Smith, IndyStar, 31 July 2025
Definition of deadly
Adjective
  • Simmons said very few improvements have been made to the highway, even as the fatal accidents continue to happen.
    — Julie Gallant, San Diego Union-Tribune, 29 July 2025
  • The 2024 case was not fatal, health department spokesperson Kimberly Harry indicated on July 28.
    — Christina Hall, Freep.com, 29 July 2025
Definition of fatal
Adjective
  • Almost every state has a variety of snake species, both poisonous and nonvenomous.
    — Janet Loehrke, USA Today, 11 July 2025
  • This Kidde portable carbon monoxide detector uses batteries and is compact enough to slip into your carry-on, giving you peace of mind that your hotel room or Airbnb is free of poisonous levels of carbon monoxide.
    — Amelia McBride, Travel + Leisure, 10 July 2025
Definition of poisonous

Browse Nearby Words

let go
lethal
lethargic
See all Nearby Words

Cite this Entry

“Lethal.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/lethal. Accessed 2 Aug. 2025.

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Nglish: Translation of lethal for Spanish Speakers

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