killer

1 of 2

noun

kill·​er ˈki-lər How to pronounce killer (audio)
1
: one that kills
2
3
a
: one that has a forceful, violent, or striking impact
b
: one that is extremely difficult to deal with

killer

2 of 2

adjective

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

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
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.
Noun
Moat did attract a sick fandom, but that sort of ugly love does not stay a killer’s hand. Helen Shaw, New Yorker, 17 Apr. 2025 Rachel’s mother Patty Morin drew an implicit parallel between her daughter’s killer and Abrego Garcia at her White House appearance, even though the latter has never been charged with a crime. Niall Stanage, The Hill, 17 Apr. 2025 Too little moisture, and there might be no botrytis activity of any kind; too much, and the collaborator becomes a killer. Saveur Editors, Saveur, 16 Apr. 2025 Detective Murphy is spooked by a theory but is determined to find all the pieces to figure out how to end the carnage of this notorious serial killer in hopes of saving another life. Zac Ntim, Deadline, 15 Apr. 2025 See All Example Sentences for killer

Word History

First Known Use

Noun

15th century, in the meaning defined at sense 1

Adjective

1951, in the meaning defined at sense 1

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

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Cite this Entry

“Killer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/killer. Accessed 24 Apr. 2025.

Kids Definition

killer

1 of 2 noun
ˈkil-ər
1
: one that kills
2

killer

2 of 2 adjective
1
: strikingly impressive or effective
a killer smile
2
: extremely difficult
a killer exam
also : causing death or devastation
a killer tornado

More from Merriam-Webster on killer

Last Updated: - Updated example sentences
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