merciless

adjective

mer·​ci·​less ˈmər-si-ləs How to pronounce merciless (audio)
Synonyms of mercilessnext
: having or showing no mercy : pitiless
the merciless killing of innocent people
mercilessly adverb
mercilessness noun

Synonyms

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Examples of merciless in a Sentence

the merciless killing of innocent people He has been merciless in his criticism of his opponent.
Recent Examples on the Web
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.
Back then, residents of the burgeoning Los Angeles area had no idea a merciless killer was lurking in their midst until Feb. 2, 1928, when the headless, naked body of a teenage boy was found in a ditch on a dusty road near the sleepy suburb of La Puente. — Kc Baker, People.com, 15 Mar. 2025 The draft being held in Pittsburgh meant the Flyers were subject to merciless booing. — Joshua Kloke, The Athletic, 8 Mar. 2025 For the last six weeks, Americans have been yanked and ghosted, lurched and launched with a merciless urgency. — Philip Elliott, TIME, 5 Mar. 2025 By enumerating the many merciless changes in our government since January, the Rev. Michael Pleger is not making a political pitch. — Chicago Tribune, 3 Mar. 2025 See All Example Sentences for merciless

Word History

First Known Use

14th century, in the meaning defined above

Time Traveler
The first known use of merciless was in the 14th century

Rhymes for merciless

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merciless
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“Merciless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/merciless. Accessed 23 Mar. 2025.

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Kids Definition

merciless

adjective
mer·​ci·​less ˈmər-si-ləs How to pronounce merciless (audio)
: having no mercy : pitiless
merciless slaughter
mercilessly adverb
mercilessness noun

More from Merriam-Webster on merciless

Nglish: Translation of merciless for Spanish Speakers

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