KILLER Synonyms: 201 Similar and Opposite Words

killer 1 of 2

noun

ˈki-lər

Definition of killer

as in headache

a dull, unpleasant, or difficult piece of work weeding out that overgrown garden is going to be a killer

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

as in murderer

a person who kills another person gunned down by hired killers

Synonyms & Similar Words

killer

2 of 2

adjective

as in lethal

likely to cause or capable of causing death killer viruses that claimed millions of lives

Synonyms & Similar Words

Antonyms & Near Antonyms

as in difficult

requiring considerable physical or mental effort a killer exercise program guaranteed to whip you into shape

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of killer

Noun

But overdoses are the biggest killer of younger people, and the change will likely have boosted US life expectancy — determined by death rates at all age groups — to another record, CNN noted. — Tom Chivers, semafor.com, 2 July 2026 The jury found that Edwin Hardeman, a California man who used the weed killer on his properties, had proved that Roundup had caused his cancer and that Monsanto had failed to warn consumers of the dangers of its product. — Sarah J. Morath, The Conversation, 2 July 2026 The Inglourious Basterds star's latest movie Ice Cream Man follows a suburb that descends into chaos when a mysterious ice cream man's treats turn children into homicidal killers. — Shyla Watson, PEOPLE, 2 July 2026 Carla Walker cold case The 1974 murder of 17-year-old Carla Walker in Fort Worth, Texas, went unsolved for more than four decades before advanced DNA testing helped investigators identify her killer. — Sarah Rumpf-Whitten, FOXNews.com, 5 July 2026 See All Example Sentences for killer

Recent Examples of Synonyms for killer

Noun

Intense exercise on a sizzling day can lead to extreme fatigue, impaired performance, headache, irritability, nausea, dizziness, cramping and dehydration, all symptoms of exertional heat illness.

— ABC News, ABC News, 3 July 2026
Hantavirus pulmonary syndrome causes fatigue, fever, muscle aches, abdominal problems, headaches, chills and dizziness in the early stages, and late symptoms include chest tightness, coughing, shortness of breath and lungs filling with fluid.

— Mary Whitfill Roeloffs, Forbes.com, 2 July 2026

Definition of headache

Noun

This psychological thriller stars Guy Pearce as Leonard Shelby, a man with anterograde amnesia struggling to track down his wife’s murderer using a system of tattoos and notes.

— Erik Kain, Forbes.com, 4 July 2026
Deputy Solicitor General Eric Feigin said blocking such searches would handicap police searching for murderers, kidnappers and robbers.

— Bart Jansen, USA Today, 29 June 2026

Definition of murderer

Adjective

The theory is that individuals became infected by a strain that was particularly lethal to the young through close contact with marmots (rodents that are known reservoirs of the plague), perhaps while butchering them.

— The Week UK, TheWeek, 6 July 2026
Hubris and risk aversion make for a lethal cocktail in high-level professional sports.

— Dieter Kurtenbach, Mercury News, 6 July 2026

Definition of lethal

Adjective

Sarah Buck, Chicago Driving has become harder The rapid increase in bike lanes has made driving much more difficult and tedious, with numerous delays due to many streets being reduced to one lane in busy areas.

— Chicago Tribune, Chicago Tribune, 5 July 2026
Republican strategists have welcomed those nominations as an opening for attack in a difficult election year.

— Susan Page, USA Today, 5 July 2026

Definition of difficult

Noun

Lee Feldman held the job for seven years until he was fired in 2018 by the commission.

— Amanda Rosa, Miami Herald, 3 July 2026
Proponents of the authorization note that the $155 million investment arrives four years after a severe drought in the Sacramento Valley in 2022 had cost local communities hundreds of millions of dollars and roughly 1,500 jobs.

— Lyanne Wang, CBS News, 2 July 2026

Definition of job

Noun

Julie has returned her old ways as an assassin, whilst navigating an equally perilous dating scene, while Edward’s honeymoon with Kayla (Shalom Brune-Franklin) doesn’t go quite as planned.

— Jesse Whittock, Deadline, 6 July 2026
In Ride or Die, Waddingham plays Judith Burton, who lives a double life as an assassin.

— Lexi Lane, PEOPLE, 5 July 2026

Definition of assassin

Adjective

When the Guadalupe River surged through Texas Hill Country last summer, Elida Sierra Lutz and her three children were swept into the deadly flooding like debris in the current.

— Alisha Ebrahimji, CNN Money, 6 July 2026
Written and directed by YouTube filmmaker Curry Barker, the film, made for $750,000, tells a twisted tale of love with deadly consequences.

— Tim Lammers, Forbes.com, 5 July 2026