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
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
Ryan Brennan,
Kansas City Star,
2 July 2026
But overdoses are the biggest killer of younger people, and the change will likely have boosted US life expectancy — determined by death rates at all age groups — to another record, CNN noted.
—
Tom Chivers,
semafor.com,
2 July 2026
Because dogs stay low and sniff constantly, fertilizers, weed killers and insecticides reach them easily.
—
Ryan Brennan,
Miami Herald,
2 July 2026
The jury found that Edwin Hardeman, a California man who used the weed killer on his properties, had proved that Roundup had caused his cancer and that Monsanto had failed to warn consumers of the dangers of its product.
—
Sarah J. Morath,
The Conversation,
2 July 2026
See All Example Sentences for killer
Examples are automatically compiled from online sources to
show current usage.
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Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
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Noun
Fertilizers, weed killers and pesticides sit right where your dog sniffs and walks.
—
Ryan Brennan,
Kansas City Star,
2 July 2026
But overdoses are the biggest killer of younger people, and the change will likely have boosted US life expectancy — determined by death rates at all age groups — to another record, CNN noted.
—
Tom Chivers,
semafor.com,
2 July 2026
Because dogs stay low and sniff constantly, fertilizers, weed killers and insecticides reach them easily.
—
Ryan Brennan,
Miami Herald,
2 July 2026
The jury found that Edwin Hardeman, a California man who used the weed killer on his properties, had proved that Roundup had caused his cancer and that Monsanto had failed to warn consumers of the dangers of its product.
—
Sarah J. Morath,
The Conversation,
2 July 2026
See All Example Sentences for killer
Cite this Entry
“Killer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/killer. Accessed 5 Jul. 2026.
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