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

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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

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as in difficult

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

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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

Other prominent killers, including Scott Peterson and the Manson family members, received death sentences that were later commuted to life in prison. — Arkansas Online, 6 Nov. 2026 The serial killer thriller follows a group of teens who knock down a drone from the sky, only to discover it contains footage of a psychopath on a killing spree. — Jack Dunn, Variety, 6 Nov. 2026 This week's set is extra good, with a 50%-off robot floor cleaner, a killer gaming headset, a nice price on an HP all-in-one desktop, and more to enjoy. — K. Thor Jensen, PC Magazine, 6 Nov. 2026 There are now three spin-off series focusing on some of the killers and a second overarching mini-series, with new killers, is planned for next year. — Borys Kit, HollywoodReporter, 6 Nov. 2026 See All Example Sentences for killer

Recent Examples of Synonyms for killer

Noun

Symptoms can include headache, fever, stiff neck and sensitivity to light.

— Kelly McGreal, FOXNews.com, 6 Nov. 2026
However, lead researcher Ferdinand Kuemmeth, an experimental physicist at the University of Regensburg and Copenhagen’s Niels Bohr Institute, argued that the technique solves a looming industrial headache.

— Aman Tripathi, Interesting Engineering, 5 Nov. 2026

Definition of headache

Noun

More than 40 years later, no efforts have been made to prosecute or extradite the presumptive murderers.

— David Ehrlich, IndieWire, 30 Oct. 2026
Alongside her scientifically credible poisoning scenarios, numerous doctors and pharmacists appear in Christie’s novels — sometimes as victims, other times as murderers — showing how her early brushes with the world of medicine never left her mind.

— Ashley Strickland, CNN Money, 29 Oct. 2026

Definition of murderer

Adjective

The state Department of Corrections and Rehabilitation does not currently have lethal injection drugs on hand, according to spokesperson Terri Hardy.

— Lia Russell, Sacbee.com, 2 Nov. 2026
Separately, his legal team has asked the governor to delay the execution and review how the state acquires drugs for lethal injections.

— ABC News, ABC News, 2 Nov. 2026

Definition of lethal

Adjective

The pilot must compensate manually using the controller, which can be difficult if the aircraft is far away or difficult to see.

— Kaif Shaikh, Interesting Engineering, 8 Nov. 2026
The chocolatey all-suede style was first released in October 2023 and has become increasingly difficult to track down over the years, with certain sizes commanding premium prices on the secondary market.

— Riley Jones, Footwear News, 7 Nov. 2026

Definition of difficult

Noun

Eco effort The hotel has achieved the highest level of BREEAM certification for its sustainability performance and has brought 650 new jobs to the area.

— Condé Nast, Condé Nast Traveler, 6 Nov. 2026
Becerra’s road to the state’s top job involved surviving a bruising June primary campaign that featured a crowded field of Democrats.

— Stephen Hobbs, Sacbee.com, 6 Nov. 2026

Definition of job

Noun

The explosion killed him and fourteen others in his vicinity, as well as the assassin, and injured another forty-three.

— Sonia Gandhi, Vanity Fair, 10 Nov. 2026
Martin McDonagh’s latest comedy drama casts Malkovich as Chris Carlisle, a dying CIA assassin who in 1973 is visiting Chile’s Easter Island with a protégé, played by Sam Rockwell, who just may kill his mentor before their getaway is over.

— The Week US, TheWeek, 10 Nov. 2026

Definition of assassin

Adjective

Putin chose to perpetrate one of his deadliest and most damaging attacks on Ukraine’s energy infrastructure at the very moment American media was singularly focused on election results.

— Bob Kustra, Chicago Tribune, 8 Nov. 2026
The Egyptian railway system, the oldest in Africa and the Middle East, has a long history of deadly accidents.

— Mostafa Salem, CNN Money, 8 Nov. 2026

Definition of deadly

Adjective

Manufacturing electronic devices from it remains difficult, particularly because reliably controlling its electrical properties through doping is challenging.

— Kaif Shaikh, Interesting Engineering, 7 Nov. 2026
Porter knew Friday’s game would be a challenging one against the Tillers.

— Steve Fryer, Oc Register, 7 Nov. 2026