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
Ian Max Stevenson, Idaho Statesman, 6 June 2024
Beginning in season 4, the show introduced C. Thomas Howell as The Reaper, a haunting killer who harbors a bizarre fascination with Hotch.
—EW.com, 6 June 2024
By record’s end, Garcia emerges in full command of this mercurial spirit world—a high priestess with a synth and a killer sixth sense.
—Suzy Exposito, SPIN, 6 June 2024
Police and Crime Stoppers of Oakland are offering up to $10,000 in reward money for information leading to the arrest of the killer.
—Harry Harris, The Mercury News, 5 June 2024
See all Example Sentences for killer 
Noun
Glyphosate, the active ingredient in Roundup, and paraquat, used in herbicides made by Syngenta, are two of the most popular weed killers in the U.S. Both have disputed links between their products and fatal diseases and have settled with plaintiffs for billions in total.
—Ian Max Stevenson, Idaho Statesman, 6 June 2024
Beginning in season 4, the show introduced C. Thomas Howell as The Reaper, a haunting killer who harbors a bizarre fascination with Hotch.
—EW.com, 6 June 2024
By record’s end, Garcia emerges in full command of this mercurial spirit world—a high priestess with a synth and a killer sixth sense.
—Suzy Exposito, SPIN, 6 June 2024
Police and Crime Stoppers of Oakland are offering up to $10,000 in reward money for information leading to the arrest of the killer.
—Harry Harris, The Mercury News, 5 June 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 9 Jun. 2024.
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