killer

1 of 2

noun

kill·​er ˈki-lər How to pronounce killer (audio)
Synonyms of killernext
1
: one that kills
2
: killer whale
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

Synonyms

Noun

Adjective

See All Synonyms & Antonyms in Thesaurus

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
More than four decades after the killings, PEOPLE is looking back at the haunting serial killer case and how it was solved with a revolutionary way of using DNA. — Sean Neumann, People.com, 12 Apr. 2025 Related article They are known as silent killers. — Taylor Nicioli, CNN Money, 12 Apr. 2025 But that killer is serving a life sentence. — Sun Sentinel Editorial Board, Sun Sentinel, 11 Apr. 2025 The killer, Mark David Chapman, stalked Lennon and had got his autograph earlier in the evening. — Sun Sentinel Editorial Board, Sun Sentinel, 11 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

Phrases Containing killer

Rhymes for killer

See All Rhymes for killer

Browse Nearby Words

killefer
killer
killer app
See all Nearby Words

Cite this Entry

“Killer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/killer. Accessed 17 Apr. 2025.

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Kids Definition

killer

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

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

Nglish: Translation of killer for Spanish Speakers

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