killer

noun
kill·​er | \ ˈki-lər How to pronounce killer (audio) \

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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Synonyms & Antonyms for killer

Synonyms: Noun

bear, beast, chore, headache, job, labor

Synonyms: Adjective

baleful, deadly, deathly, fatal, fell, lethal, mortal, murderous, pestilent, terminal, vital

Antonyms: Adjective

healthful, healthy, nonfatal, nonlethal, wholesome

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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

The serial killer, Craig has said, appears to have lured women into vacant buildings, raped and then killed them. Frank Witsil, Detroit Free Press, "Person of interest in Detroit serial killings charged in sexual assault," 10 June 2019 Gary Ridgway, known as the Green River Killer, is thought to be the country’s deadliest serial killer in terms of guilty pleas, with 49 victims. Washington Post, The Denver Post, "Convicted California murderer now linked to more than 60 deaths may be most prolific killer in U.S. history," 9 June 2019 But while police had identified the killer, the names of those four victims remained unknown until now. Andrew Liptak, The Verge, "How a podcast helped solve a grisly cold case," 9 June 2019 Gary Ridgway, known as the Green River Killer, is thought to be the country’s deadliest serial killer in terms of guilty pleas, with 49 victims. The Washington Post, The Mercury News, "Convicted California murderer now linked to more than 60 deaths may be most prolific killer in US history," 9 June 2019 Gary Ridgway, known as the Green River Killer, is thought to be the country’s deadliest serial killer in terms of guilty pleas, with 49 victims. Alex Horton, Washington Post, "Convicted murderer now linked to more than 60 deaths may be most prolific killer in U.S. history," 8 June 2019 By now Wick, the contract killer played by Keanu Reeves, has endured, and must avenge, countless insults to his... Joe Morgenstern, WSJ, "‘John Wick: Chapter 3—Parabellum’ Review: Elegant Escapism," 16 May 2019 Traction control, that burnout-squelching fun-killer, is saving the day out here. Ezra Dyer, Popular Mechanics, "The Kia Telluride Has Some Serious Off-Road Chops," 7 May 2019 When Moose gets shot by the killer, the green-eyed theme comes back again. Carolyn Twersky, Seventeen, "9 "Riverdale" Plot Holes That Will Keep You Up at Night," 3 May 2019

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

16 Jun 2019

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
informal : something that is very difficult

killer

adjective

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

chiefly US
: causing death or destruction
informal : very impressive or appealing
informal : very difficult

killer

noun
kill·​er | \ ˈki-lər How to pronounce killer (audio) \

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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More from Merriam-Webster on killer

Rhyming Dictionary: Words that rhyme with killer

Thesaurus: All synonyms and antonyms for killer

Spanish Central: Translation of killer

Nglish: Translation of killer for Spanish Speakers

Britannica English: Translation of killer for Arabic Speakers

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