merciless

adjective

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

Synonyms of merciless

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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.
It would be seen as a work of merciless autofiction in the vein of Karl Ove Knausgaard, and it would be discussed, as his books are, as aggressive, antisocial, and spiteful. — B. D. McClay, New Yorker, 19 Oct. 2026 In the story, Ria teams up with her foster mother and their fellow punks to resist a merciless developer intent on tearing down their building. — Naman Ramachandran, Variety, 19 Oct. 2026 The book’s humor is sharp and merciless, akin to that of a standup comedy show, and yet the things described are far from funny. — Literary Hub, 14 Oct. 2026 Cora, the granddaughter of a woman kidnapped from West Africa and sold into slavery, flees her captor’s plantation, plunging her into the book’s alternate steampunk reality where she is pursued by the merciless slave catcher Ridgeway. — David Faris, TheWeek, 16 Sep. 2026 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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Browse Nearby Words

mercifulness
merciless
mercuhydrin
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Cite this Entry

“Merciless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/merciless. Accessed 20 Oct. 2026.

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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
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