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Synonyms

lethality

American  
[lee-thal-i-tee] / liˈθæl ɪ ti /
Also lethalness

noun

  1. the capacity to cause great harm, destruction, or death.

    Many pathogens are self-limited by their own lethality—the host dies before it has a chance to spread the pathogen.

  2. the likelihood of causing great harm, destruction, or death.

    Mutations can increase or decrease lethality, but most viruses mutate to less lethal forms.

  3. death.

    Prion diseases, such as so-called “mad cow,” are characterized by neurodegeneration and lethality.


Etymology

Origin of lethality

lethal ( def. ) + -ity ( def. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

On March 2, 2026, after bragging about the awe-inspiring lethality of U.S.

From Salon • Mar. 10, 2026

Earlier research has shown that the pain caused by stinging insects does not always match the lethality of their venom.

From Science Daily • Dec. 4, 2025

The U.S. is building a “Qatari Emiri Air Force facility,” Hegseth said, “to enhance our combined training, increase the lethality and interoperability.”

From The Wall Street Journal • Oct. 11, 2025

"The location will host a contingent of Qatari F-15s and pilots to enhance our combined training" as well as "increase lethality, interoperability," he said.

From Barron's • Oct. 11, 2025

Although, by then, technological advances to conventional military capabilities seemed to be approaching the destructive power, or more precisely, the system lethality of nuclear weapons.

From Shock and Awe — Achieving Rapid Dominance by Wade, James P.