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

But after Brady returned to Maryland and said Boblit was the real killer, officers confronted him once again. Longreads, "The Bungled Bank Robbery That Ended in a Landmark Legal Ruling," 26 June 2018 And there’s like a bunch of random strangers, one of who might be a serial killer, OK, great. Jeet Heer, The New Republic, "Elon Musk hates trains and will now build them for Chicago.," 14 June 2018 And there’s like a bunch of random strangers, one of who might be a serial killer, OK, great. Eben Weiss, Outside Online, "Let's Fire Elon Musk Into Space," 31 May 2018 Block out a special time The thrill of getting caught may be hot under certain circumstances, but chances are, knowing someone might walk in any minute will be a mood-killer, says Mintz. Suzannah Weiss, Glamour, "The Best 7 Masturbation Tips to Get You Super Turned On When You're Solo," 23 Mar. 2019 In particular, the formerly timid Eve is now officially a stone-cold killer. Katherine J. Igoe, Marie Claire, "'Killing Eve' Season Two Finally Has a Release Date. Here's Everything We Know.," 5 Jan. 2019 The battery life is the real killer for this phone. Ron Amadeo, Ars Technica, "Palm Phone Review: Fun, endearing, and bad at everything," 1 Dec. 2018 While the costume itself was killer, her yellow-colored skin was streaky and unevenly applied. Avery Matera, Teen Vogue, "Emily Ratajkowski Wore a Fur Bikini for a “One Million Years B.C” Halloween Costume," 1 Nov. 2018 As the power of artificial intelligence grows, the likelihood of a future war filled with killer robots grows as well. David Hambling, Popular Mechanics, "Why the U.S. Is Backing Killer Robots," 14 Sep. 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

21 Apr 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

Comments on killer

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