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 of killer

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Noun

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
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Noun
For the third-act interrogation scene of Longlegs, the horror-mystery’s occult obsessed serial killer (played by Nicolas Cage in heavy prosthetic makeup) punctuates his free-associative jailhouse ramblings with a stunning act of self-annihilation. — Chris Lee, Vulture, 30 Oct. 2026 When a missing kid who had been previously linked to the notorious serial killer Jurek Walter (Stephen Graham) reappears after several years, Jonah dusts off his badge. — Aramide Tinubu, Variety, 30 Oct. 2026 For Klaas, whose daughter’s killer, Richard Allen Davis, remains on death row, a blanket commutation would deny families the justice recommended by juries and imposed by judges. — Louis Casiano, FOXNews.com, 29 Oct. 2026 Adapted from Lars Kepler’s bestselling novel, the series centers on Schreiber’s ex-cop whose move to a small western Pennsylvania town spurs a string of disappearances possibly tied to a serial killer. — Alexandra Del Rosario, Los Angeles Times, 29 Oct. 2026 See All Example Sentences for killer

Word History

First Known Use

Noun

15th century, in the meaning defined at sense 1

Adjective

1939, in the meaning defined at sense 2

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 1 Nov. 2026.

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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
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