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
Jonathan Tirone, Fortune Europe, 30 Apr. 2024
The tech giant’s Prime Video streaming platform has ordered a second season of Cross, a drama starring Aldis Hodge and based on James Patterson’s best-selling novel series about a detective and forensic psychologist who delves into the minds of killers in order to catch them.
—Rick Porter, The Hollywood Reporter, 30 Apr. 2024
See all Example Sentences for killer 
Noun
Spreading global conflict combined with financial incentives for companies to promote AI adds to the challenge of controlling killer robots, according to Jaan Tallinn, an early investor in Alphabet Inc.’s AI platform DeepMind Technologies.
—Jonathan Tirone, Fortune Europe, 30 Apr. 2024
The tech giant’s Prime Video streaming platform has ordered a second season of Cross, a drama starring Aldis Hodge and based on James Patterson’s best-selling novel series about a detective and forensic psychologist who delves into the minds of killers in order to catch them.
—Rick Porter, The Hollywood Reporter, 30 Apr. 2024
See all Example Sentences for killer
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'killer.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Dictionary Entries Near killer
Cite this Entry
“Killer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/killer. Accessed 3 May. 2024.
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