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
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
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
Pete Sampson, The Athletic, 23 Jan. 2025
The real killer, Rudy Guede, got off with a light sentence.
—Audrey Conklin, Fox News, 23 Jan. 2025
Two brothers who were convicted in the 1991 rape and murder of a tourist in Hawaii filed a federal lawsuit on Tuesday claiming that the police had framed them and then bungled an investigation that could have brought the true killer to justice.
—Simon J. Levien, New York Times, 23 Jan. 2025
After decades of lycanthropy, Sir John is no longer a reluctant killer and has stopped chaining himself up during the full moon, now gleefully slaughtering innocents without a care in the world.
—Louis Peitzman, Vulture, 22 Jan. 2025
See all Example Sentences for killer 
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Noun
No Rylie Mills, Boubacar Traore or Jordan Botelho with a limited Howard Cross turned into a game-plan killer for Al Golden.
—Pete Sampson, The Athletic, 23 Jan. 2025
The real killer, Rudy Guede, got off with a light sentence.
—Audrey Conklin, Fox News, 23 Jan. 2025
Two brothers who were convicted in the 1991 rape and murder of a tourist in Hawaii filed a federal lawsuit on Tuesday claiming that the police had framed them and then bungled an investigation that could have brought the true killer to justice.
—Simon J. Levien, New York Times, 23 Jan. 2025
After decades of lycanthropy, Sir John is no longer a reluctant killer and has stopped chaining himself up during the full moon, now gleefully slaughtering innocents without a care in the world.
—Louis Peitzman, Vulture, 22 Jan. 2025
See all Example Sentences for killer
Dictionary Entries Near killer
Cite this Entry
“Killer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/killer. Accessed 28 Jan. 2025.
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