fatal

American  

[feyt-l] / ˈfeɪt l /

adjective

1. causing or capable of causing death; mortal; deadly.

   a fatal accident;

   a fatal dose of poison.

   Antonyms:

   life-giving

2. causing destruction, misfortune, ruin, or failure.

   The withdrawal of funds was fatal to the project.

   Synonyms:

   devastating, catastrophic, calamitous, disastrous, ruinous

3. decisively important; fateful.

   The fatal day finally arrived.

4. proceeding from or decreed by fate; inevitable.

   a fatal series of events.

5. influencing or concerned with fate; fatalistic.

6. Obsolete. condemned by fate; doomed.

7. Obsolete. prophetic.

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fatal British  

/ ˈfeɪtəl /

adjective

1. resulting in or capable of causing death

   a fatal accident

2. bringing ruin; disastrous

3. decisively important; fateful

4. decreed by fate; destined; inevitable

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Usage

What does fatal mean? Fatal literally means deadly—capable of causing death. Similar words are deadly, lethal, and mortal—though they are often used in different ways. Fatal can also be used in a figurative way to mean capable of causing the destruction, ruin, or failure of someone or something, as in Failing to update their products proved to be a fatal mistake for the company. Example: These changes will hopefully greatly reduce the number of fatal car accidents that occur on highways.

Related Words

Fatal, deadly, lethal, mortal apply to something that has caused or is capable of causing death. Fatal may refer to either the future or the past; in either case, it emphasizes inevitability and the inescapable—the disastrous, whether death or dire misfortune: The accident was fatal. Such a mistake would be fatal. Deadly looks to the future, and suggests that which is likely to cause death (though not inevitably so): a deadly poison, disease. Like deadly, lethal looks to the future but, like many other words of Latin origin, suggests a more technical usage: a lethal dose; a gas that is lethal. Mortal looks to the past and refers to death that has actually occurred: He received a mortal wound. The disease proved to be mortal.

Other Word Forms

• fatalness noun
• nonfatal adjective
• nonfatally adverb
• nonfatalness noun
• quasi-fatal adjective
• quasi-fatally adverb

Etymology

Origin of fatal

First recorded in 1350–1400; Middle English or directly from Old French, from Latin fātālis “ordained by fate, decreed”; see origin at fate, -al ¹

Explanation

The adjective fatal describes something that is capable of causing death. Certain cleaning products, for instance, are labeled, “Could be fatal if swallowed.” Here's a helpful suggestion: don't swallow them. Can you hear the word fate in fatal? In ancient times, people believed that the future was determined by a force called fate, and in the 14th century, the French used the word fatal to describe anything that fate had decreed, including death. By the next century the word had evolved to mean something that specifically causes death. Today the term is used more loosely. If your friend makes a fatal mistake on the tennis court, it doesn't mean that he'll literally die, just that he'll lose the game.

Example Sentences

Asked what went wrong with Calocane's care in the community, he said he had learned 95% of what he knew about Calocane since the fatal attacks in June 2023.

From BBC • Apr. 30, 2026

Now powered by extensive charging and battery-swapping infrastructure, the cost structures clearly favour electric models, experts say, in a potentially fatal blow for conventional diesel rigs.

From Barron's • Apr. 29, 2026

“Speeding continues to be one of the leading causes of serious and fatal crashes on California’s roadways,” CHP Commissioner Sean Duryee said in the release.

From Los Angeles Times • Apr. 28, 2026

Films like “Ready or Not 2: Here I Come,” on the other hand, present marriage as a potentially fatal error that begins the moment a woman says, “I do.”

From Salon • Apr. 23, 2026

They didn’t notice that he’d hurt me and they didn’t notice that I do make fatal small mistakes from time to time.

From "Code Name Verity" by Elizabeth Wein

Related Words

• calamitous
• cataclysmic
• catastrophic
• destructive
• disastrous
• fateful
• incurable
• inevitable
• malignant
• mortal
• poisonous
• ruinous
• virulent