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

The death penalty is intended for the worst of the worst killers, defense lawyer Samuel Halpern told a jury Friday morning. Rafael Olmeda, Sun-Sentinel.com, "Final plea for mercy before jury weighs death penalty in murder of Broward deputy," 13 July 2018 An $8,100 reward has been offered for information that leads to the arrest of a wolf killer, the German Organization for the Protection of Wolves announced on Wednesday. Deutsche Welle, USA TODAY, "Wolf fatally shot, tied to weight and dumped in lake," 12 July 2018 Tuberculosis, an airborne infection, is one of the world’s biggest infectious disease killers, mostly in low- and middle-income countries. Betsy Mckay, WSJ, "Johns Hopkins Evacuates Two Lab Buildings After Tuberculosis Scare," 5 July 2018 His first inning -- the sixth -- was the killer, as the Reds scored five times against him, with four coming on a José Peraza grand slam. Todd Rosiak, Milwaukee Journal Sentinel, "Brewers once again demote struggling shortstop Orlando Arcia," 1 July 2018 Ohnesorg’s killer had been an unmarked police officer, later acquitted. The Economist, "The legacy of Germany’s student protests in 1968," 31 May 2018 Stay tuned for a chat with biotech investor Brad Loncar about Hong Kong’s impending biotech boom, a discussion of how consumer genetic testing relates to serial killers, and an exploration of Big Biotech’s existential crises. Damian Garde, STAT, "LISTEN: Chinese biotech bubbles, activist investors, & Bill Gates’s flu frugality," 3 May 2018 Theories abound, but what happened that night and who the killers are still remain a mystery. Cameron Knight, Cincinnati.com, "Artist paints Rhoden family in campaign against gun violence," 1 May 2018 Victims of a notorious Northern California serial killer and rapist traveled to California's capital city Thursday to get their first glimpse of the man facing charges in connection with the long-ago attacks. Amy Lieu, Fox News, "'Golden State Killer' suspect faces victims, families at court hearing," 13 July 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

6 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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