Synonyms & Antonyms of lethal

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Frequently Asked Questions About lethal

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

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Time Traveler for lethal

Time Traveler

The first known use of lethal was circa 1604

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Thesaurus Entries Near lethal

let go



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Cite this Entry

“Lethal.” Thesaurus, Merriam-Webster, Accessed 21 Jan. 2022.

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More from Merriam-Webster on lethal

Nglish: Translation of lethal for Spanish Speakers

Britannica English: Translation of lethal for Arabic Speakers


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