DEADLY Synonyms: 324 Similar and Opposite Words

Q: 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

Q: 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

Q: 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

Q: 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

deadly 1 of 2

adjective

ˈded-lē

Definition of deadly next

as in lethal

likely to cause or capable of causing death the doctors were alarmed about the outbreak of the deadly new virus

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

as in sheer

having no exceptions or restrictions the deadly tedium of waiting for the fog to lift

Synonyms & Similar Words

Antonyms & Near Antonyms

as in mortal

of, relating to, or suggestive of death a deadly pallor spread across her face as the tragic news gradually sank in

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deadly

2 of 2

adverb

as in extremely

to a great degree I'm deadly serious about making an offer on the house

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Antonyms & Near Antonyms

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

Examples 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

Organic carrots and celery sold at Whole Foods Market in five states are being recalled amid a deadly E. coli outbreak that has stricken 39 people in 18 states. —

Kate Gibson, CBS News, 22 Nov. 2024 DeGeneres posted video of the surging waters behind her home in January 2023, which arrived on the five-year anniversary of deadly mudslides in the area. —

Amy Hubbard, Los Angeles Times, 21 Nov. 2024

Adverb

Guy does not take him seriously, but Bruno is deadly serious. —

Duante Beddingfield, Detroit Free Press, 25 Oct. 2024 Some seemed deadly dull, repetitive, or irrelevant. —

Steven Levy, WIRED, 4 Oct. 2024 See all Example Sentences for deadly

Recent Examples of Synonyms for deadly

Adjective

The arachnids have become the lethal poisonous animal in Brazil and has increased the demand for antivenom.

Laura Baisas, Popular Science, 7 Nov. 2024
Snares, set to capture other animals for bushmeat, pose a lethal risk to saolas, who often fall victim to these traps accidentally. Cheap and easy to deploy, snares blanket the forests, endangering not just the saola but a wide range of species.

Scott Travers, Forbes, 5 Nov. 2024