kill·​er | \ ˈki-lər How to pronounce killer (audio) \

Definition of killer

 (Entry 1 of 2)

1 : one that kills
3a : one that has a forceful, violent, or striking impact
b : one that is extremely difficult to deal with



Definition of killer (Entry 2 of 2)

1 : strikingly impressive or effective a killer smile a killer résumé
2 : extremely difficult to deal with a killer fastball also : causing death or devastation a killer tornado

Synonyms & Antonyms for killer

Synonyms: Noun

Synonyms: Adjective

Antonyms: Adjective

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Examples of killer in a Sentence

Noun Heart disease is the leading killer of both men and women. The chemical is used as a weed killer. Adjective killer viruses that claimed millions of lives a killer exercise program guaranteed to whip you into shape
Recent Examples on the Web: Noun The police department, the employer of Daunte Wright's killer before the officer resigned last year, also released body camera video and audio from the scene of the highway confrontation. Dennis Romero, NBC News, 9 May 2022 Patsy holds up a reward sign for information leading to the arrest of their daughter's killer. Caitlin O'kane, CBS News, 2 May 2022 The manhunt for the 51-year-old mother of two's killer continued three days after her remains were discovered inside a duffel bag less than a mile from her Juno Street home. Stephanie Pagones, Fox News, 19 Apr. 2022 According to the logline for the show, Batman Unburied will begin with Wayne working as a forensic pathologist in Gotham Hospital, examining the victims of a serial killer known as The Harvester. J. Clara Chan, The Hollywood Reporter, 5 Apr. 2022 For more than three decades, the identity of the serial killer who prowled Interstate 65 up and down Indiana and Kentucky, raping and murdering women in roadside hotels, has been a mystery. Until now. Jake Allen, The Indianapolis Star, 5 Apr. 2022 Speaking of killer, her performance's shadowy suburban backdrop was giving us major Nightmare on Elm Street vibes. Leah Greenblatt,, 4 Apr. 2022 But news of a serial killer in the area sets off alarm bells. Los Angeles Times, 19 Mar. 2022 During the investigation of her murder, detectives zeroed in on two small marks on the upper part of her right arm – possible bite marks that could match the teeth of the killer. al, 8 Mar. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'killer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of killer


15th century, in the meaning defined at sense 1


1951, in the meaning defined at sense 1

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Time Traveler for killer

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The first known use of killer was in the 15th century

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killer app

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Statistics for killer

Last Updated

13 May 2022

Cite this Entry

“Killer.” Dictionary, Merriam-Webster, Accessed 16 May. 2022.

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More Definitions for killer


kill·​er | \ ˈki-lər How to pronounce killer (audio) \

Kids Definition of killer

 (Entry 1 of 2)

: someone or something that takes the life of a person or animal



Kids Definition of killer (Entry 2 of 2)

1 : very impressive or effective a killer smile
2 : very difficult a killer exam
3 : causing death or ruin a killer tornado

More from Merriam-Webster on killer

Nglish: Translation of killer for Spanish Speakers

Britannica English: Translation of killer for Arabic Speakers


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