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

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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

Serial killers and stalkers find love, sometimes with their targets. — Clare Mulroy, USA Today, 18 July 2026 If Russia moves in this direction, a nuclear detonation in low-Earth orbit could be the ultimate Starlink killer. — Stephen Clark, ArsTechnica, 16 July 2026 Scattered on the dunes, the surviving population of Gaza was reduced to bare existence, subject to unrelenting hunger and thirst under the ever-present hum of killer drones and bomber jets. — Literary Hub, 16 July 2026 While the recent identification of her body brings closure to Gaston’s disappearance, her killer has already been incarcerated for years. — Eleanor Jacobs, PEOPLE, 16 July 2026 See All Example Sentences for killer

Recent Examples of Synonyms for killer

Noun

Around one in 13 people experience recurring morning headaches, research suggests, with women and those between the ages of 45 and 64 more likely to have them.

— Kathleen Felton, Washington Post, 17 July 2026
As body temperature rises and humidity limits the body’s ability to cool itself, mild symptoms such as cramps and headaches can progress to shortness of breath, dizziness, confusion, nausea, and ultimately life-threatening heat stroke.

— Laura Schifter, Time, 17 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
The voice cast is a murderer's row of famous Australians, including Sarah Snook, Eric Bana, and Nick Cave.

— Jordan Hoffman, Entertainment Weekly, 1 July 2026

Definition of murderer

Adjective

Mbappe was so dynamic, so consistently a threat even when the ball was 50 yards away, and so lethal except for that one day in Dallas.

— Adam Crafton, New York Times, 20 July 2026
After lighting the fire, Arrabaca also pulled out an airsoft rifle — a device commonly used in sports and recreation resembling a gun, but fires less lethal projectiles rather than bullets — and fired five to seven pellets, officials said.

— Brynn Gingras, CNN Money, 20 July 2026

Definition of lethal

Adjective

Unlike dogs, they cannot simply be taken on longer walks, often resist dietary changes, and can be difficult to medicate consistently, making GLP-1 therapies potentially attractive if clinical trials prove successful.

— Elsa Ohlen,Carolin Roth, CNBC, 18 July 2026
Their stories recount the devastation to homes and businesses, life in temporary shelters, and the difficult process of rebuilding or relocating.

— Michelle Oliva-Espinosa, Kansas City Star, 18 July 2026

Definition of difficult

Noun

Felicia Schlafer received tickets to the USA Dream Team basketball game through her job.

— Andrea Clement, AJC.com, 17 July 2026
Excellent job, acknowledges both her physical transformation and that her mouth can get her into more trouble than mine does at the underwear party in Fire Island.

— Brian Moylan, Vulture, 17 July 2026

Definition of job

Noun

By the time Cameron came up with the idea for The Terminator — about a robot assassin sent back in time to kill the mother of humanity’s unborn savior — Wisher was growing more interested in screenwriting.

— Jon Blistein, Rolling Stone, 21 July 2026
Their characters — a notorious assassin and a lawyer — race across Europe, balancing brutal fights and a messy, decades-long friendship.

— Emily Zemler, Los Angeles Times, 16 July 2026

Definition of assassin

Adjective

And now Iran has shown US troops face those same dangers around the region – with deadly consequences.

— Hanna Ziady, CNN Money, 20 July 2026
The war has also affected fertilizer supplies and prices, threatening the planting season and worsening the fate of mostly farming communities in northern Nigeria who have struggled to access their farmlands amid a deadly conflict with armed groups.

— ABC News, ABC News, 19 July 2026

Definition of deadly

Adjective

The method also relies on multiple Bell tests and assumptions about independent quantum sources, which could make large-scale implementation challenging.

— Rupendra Brahambhatt, Interesting Engineering, 18 July 2026
His 15-point first half Thursday included two threes, a high-degree-of-difficulty turnaround jumper and another challenging jumper.

— Barry Jackson, Miami Herald, 17 July 2026