killer

noun
kill·​er | \ˈki-lər \

Definition of killer 

(Entry 1 of 2)

1 : one that kills

3a : one that has a forceful, violent, or striking impact

b : one that is extremely difficult to deal with

killer

adjective

Definition of killer (Entry 2 of 2)

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

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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
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Recent Examples on the Web: Noun

Police hope the profile will provide a break in finding Linda’s killer. Timesoc, latimes.com, "TimesOC: Police release DNA snapshot of possible suspect in girl’s 1973 slaying," 11 July 2018 This group of kids band together and create their own murder investigation squad, which apparently leads them to suspecting the killer is a cop, Officer Mackey. refinery29.com, "Summer Of ‘84 Brings Us More ‘80s Thrills Nostalgia For Stranger Things Fans," 1 July 2018 Tacoma police hire a genetic genealogist to test DNA sample from Welch’s killer. Stacia Glenn, The Seattle Times, "DNA, used napkin lead police to suspect in Tacoma girl’s 1986 killing," 25 June 2018 Marie Crawford expressed happiness that her daughter’s killer had finally been brought to justice. David Owens, courant.com, "Hartford Man Convicted Of Killing Two Women Pleads Guilty To Killing Two More," 22 June 2018 Byron Baker said his mother regularly asks whether investigators have any updates on Cheryl’s killer. Nicole Blanchard And Ruth Brown, idahostatesman, "He left behind 3 dead women & disappeared. Friends, family & the law still seek answers.," 15 June 2018 The killer is a shiny green insect from Asia called the emerald ash borer. Frank Fitzpatrick, Philly.com, "Ashes of an industry: A Pennsylvania tradition is dying, one baseball bat at a time," 14 June 2018 In their former lives, these killers were nets and other fishing gear essential to the livelihoods of millions around the world, and put food on the plates of millions more. Elena Bectoros, The Christian Science Monitor, "Divers help to remove abandoned, destructive 'ghost' nets," 8 June 2018 Johnny Depp is on the hunt for Notorious B.I.G.’s killer in the first trailer for his new movie, City of Lies. Mike Miller, PEOPLE.com, "Watch Johnny Depp Hunt for Notorious B.I.G.'s Killer in First Trailer for City of Lies," 21 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'killer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of killer

Noun

15th century, in the meaning defined at sense 1

Adjective

1951, in the meaning defined at sense 1

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Dictionary Entries near killer

killed

Killeen

killefer

killer

killer app

killer bar

killer bee

Statistics for killer

Last Updated

20 Oct 2018

Look-up Popularity

Time Traveler for killer

The first known use of killer was in the 15th century

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More Definitions for killer

killer

noun

English Language Learners Definition of killer

 (Entry 1 of 2)

: a person or thing that kills someone or something

: something that is very difficult

killer

adjective

English Language Learners Definition of killer (Entry 2 of 2)

: causing death or destruction

: very impressive or appealing

: very difficult

killer

noun
kill·​er | \ˈki-lər \

Kids Definition of killer

 (Entry 1 of 2)

: someone or something that takes the life of a person or animal

killer

adjective

Kids Definition of killer (Entry 2 of 2)

1 : very impressive or effective a killer smile

2 : very difficult a killer exam

3 : causing death or ruin a killer tornado

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Comments on killer

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