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
Chad De Guzman, Time, 18 Sep. 2025
The 22-year-old from southern Utah evolved from a top high school student to a scholarship recipient to an alleged killer.
—Michael Ruiz , Sarah Rumpf-Whitten, FOXNews.com, 17 Sep. 2025
Judge tosses two murder charges related to acts of terrorism against Luigi Mangione, the alleged killer of UnitedHealthcare’s CEO last year.
—Amy Feldman, Forbes.com, 17 Sep. 2025
And, of course, such studies do not fully explain why some kids can watch gore or play violent video games without any problems, and other kids allegedly turn into killers because of them.
—Jay Caspian Kang, New Yorker, 17 Sep. 2025
See All Example Sentences for killer
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
This is not about one comment about Charlie Kirk’s killer.
—Chad De Guzman, Time, 18 Sep. 2025
The 22-year-old from southern Utah evolved from a top high school student to a scholarship recipient to an alleged killer.
—Michael Ruiz , Sarah Rumpf-Whitten, FOXNews.com, 17 Sep. 2025
Judge tosses two murder charges related to acts of terrorism against Luigi Mangione, the alleged killer of UnitedHealthcare’s CEO last year.
—Amy Feldman, Forbes.com, 17 Sep. 2025
And, of course, such studies do not fully explain why some kids can watch gore or play violent video games without any problems, and other kids allegedly turn into killers because of them.
—Jay Caspian Kang, New Yorker, 17 Sep. 2025
See All Example Sentences for killer
Cite this Entry
“Killer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/killer. Accessed 18 Sep. 2025.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
Share