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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.

See Examples For:

In laboratory experiments, blocking E2F3 prevented tumor growth through a process known as "synthetic lethality."

From Science Daily Jul. 4, 2026

He added: "The navy plan will be a good one - dispersed lethality makes a lot of sense today".

From BBC Jun. 29, 2026

That surge in lethality underscores the potency of the high-tech but cheaply made drones.

From Los Angeles Times May 24, 2026

In contrast, the lethality of new world viruses can exceed 40 percent.

From Barron's May 4, 2026

His face was sphinx-like in its immobility but the cold lethality of his eyes was apparent even to the inexperienced tenderfoot, who was growing strangely uncomfortable for some indefinable reason.

From The Song of the Wolf by Frank Mayer

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