fatal

adjective

fa·​tal ˈfā-tᵊl How to pronounce fatal (audio)
1
a
: causing death
a fatal crash
a fatal disease
a fatal wound
b
: bringing ruin
a fatal attraction to gambling
c
: causing failure
a fatal design flaw
Lack of sufficient support was fatal to his campaign.
2
a
: determining one's fate
the fatal flaw in this dazzling woman: a total lack of tasteMarya Mannes
b
: of or relating to fate
… this science sets a fatal necessity on things …H. O. Taylor
c
: resembling fate in proceeding according to a fixed sequence
3
: fateful
a fatal hour
4
obsolete : fated
Choose the Right Synonym for fatal

deadly, mortal, fatal, lethal mean causing or capable of causing death.

deadly applies to an established or very likely cause of death.

a deadly disease

mortal implies that death has occurred or is inevitable.

a mortal wound

fatal stresses the inevitability of what has in fact resulted in death or destruction.

fatal consequences

lethal applies to something that is bound to cause death or exists for the destruction of life.

lethal gas

Examples of fatal in a Sentence

a disease that is often fatal a chemical that can be fatal to birds She made a fatal mistake.
Recent Examples on the Web
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.
Unlike chronic wasting diease, hemorrhagic disease is not always fatal. Kirsten Fiscus, Nashville Tennessean, 5 Oct. 2025 The Basil Pesto Bowtie Salad and Smoked Mozzarella Penne Salad may be contaminated by bacteria listeria monocytogenes, which can cause fatal infections in children, the elderly and those with weakened immune systems, according to a news release from Kroger. Matthew Cupelli, Cincinnati Enquirer, 4 Oct. 2025 Authorities have charged Harjinder Singh, a Sikh, and the truck driver in the fatal crash, with vehicular homicide. Milena Malaver, Miami Herald, 4 Oct. 2025 That is how Katie Hamilton, the sister of Thomas Jacob Sanford, the man police say launched a fatal attack on The Church of Jesus Christ of Latter-day Saints in Grand Blanc Township, describes the Mormons and many others contributing to a fundraiser to help her family. Leah Olajide, Freep.com, 3 Oct. 2025 See All Example Sentences for fatal

Word History

Etymology

Middle English, from Latin fatalis, from fatum fate

First Known Use

14th century, in the meaning defined at sense 4

Time Traveler
The first known use of fatal was in the 14th century

Browse Nearby Words

Cite this Entry

“Fatal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fatal. Accessed 9 Oct. 2025.

Kids Definition

fatal

adjective
fa·​tal ˈfāt-ᵊl How to pronounce fatal (audio)
1
: deciding one's fate : fateful
on that fatal day
2
: causing death or ruin
a fatal accident
fatally
-ᵊl-ē
adverb

Medical Definition

fatal

adjective
fa·​tal ˈfāt-ᵊl How to pronounce fatal (audio)
: causing death
a fatal diabetic comaHavelock Ellis
fatally adverb

Legal Definition

fatal

adjective
fa·​tal
1
: causing failure of a legal claim or cause of action
a fatal defect in the proceedingsW. R. LaFave and J. H. Israel
2
: making something (as a contract) invalid or unenforceable
there is a fatal indefiniteness with the result that the agreement is voidJ. D. Calamari and J. M. Perillo
fatally adverb

More from Merriam-Webster on fatal

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