thoughtless

adjective

thought·​less ˈthȯt-ləs How to pronounce thoughtless (audio)
Synonyms of thoughtless
1
: lacking concern for others : inconsiderate
rude and thoughtless behavior
a thoughtless remark
2
a
: insufficiently alert : careless
b
: reckless, rash
thoughtless actions
3
: devoid of thought : insensate
thoughtlessly adverb
thoughtlessness noun

Synonyms of thoughtless

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Examples of thoughtless in a Sentence

a selfish and thoughtless person always making thoughtless comments that hurt other people's feelings
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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.
At the outset of this chatty novel, the protagonist, Caroline, who was recently ghosted by a thoughtless man, has had a story published in this magazine. — The New Yorker, New Yorker, 10 Aug. 2026 That self-deprecating description opens Tony, writer-director Matt Johnson’s movie about the one crazy summer that changed a thoughtless young lout’s life; for good measure, the quote does double duty as the tagline on the film’s poster. — David Fear, Rolling Stone, 5 Aug. 2026 This tragedy serves as a powerful reminder that no family should have to bury a child because of someone’s thoughtless and irresponsible choices. — Grethel Aguila, Miami Herald, 23 June 2026 This rhetoric is not just the thoughtless ramblings of mindless partisans. — Chris Roemer, Baltimore Sun, 30 Apr. 2026 See All Example Sentences for thoughtless

Word History

First Known Use

1544, in the meaning defined at sense 2a

Time Traveler
The first known use of thoughtless was in 1544

Rhymes for thoughtless

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Browse Nearby Words

thoughtful
thoughtless
thoughtlet
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Cite this Entry

“Thoughtless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thoughtless. Accessed 1 Sep. 2026.

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Kids Definition

thoughtless

adjective
thought·​less ˈthȯt-ləs How to pronounce thoughtless (audio)
1
a
: not careful and alert
b
: done without thinking beforehand
thoughtless actions
2
: lacking concern for others : inconsiderate
a thoughtless remark
thoughtlessly adverb
thoughtlessness noun
Last Updated: - Updated example sentences
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