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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

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.
Despite the Hulu show earning merciless reviews, Close doesn’t blame Kimmy’s (lack of) talent. Jason P. Frank, Vulture, 20 Nov. 2025 What isn’t, based on early returns, is the merciless, ruthless approach toward inferior competition. Mark Zeigler, San Diego Union-Tribune, 8 Nov. 2025 At face value, the Predator–its appearance, its tactics, its merciless killing spree–is the common thread that ties these four pictures together. Andy Crump, Time, 7 Nov. 2025 Following the deaths of his brother William (Felix Kammerer) and his sister-in-law Elizabeth (Mia Goth), Victor vows vengeance on the Creature and dedicates the rest of his life to a merciless pursuit of him. Yasmeen Hamadeh, PEOPLE, 7 Nov. 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

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Cite this Entry

“Merciless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/merciless. Accessed 5 Dec. 2025.

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

Last Updated: - Updated example sentences
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