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Synonyms

thoughtless

American  
[thawt-lis] / ˈθɔt lɪs /

adjective

  1. lacking in consideration for others; inconsiderate; tactless.

    a thoughtless remark.

    Synonyms:
    neglectful, negligent
  2. characterized by or showing lack of thought.

    a shallow, thoughtless book.

  3. not thinking enough; careless or heedless.

    thoughtless of his health.

    Synonyms:
    remiss, inattentive
  4. devoid of or lacking capacity for thought.


thoughtless British  
/ ˈθɔːtlɪs /

adjective

  1. inconsiderate

    a thoughtless remark

  2. having or showing lack of thought

    a thoughtless essay

  3. unable to think; not having the power of thought

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of thoughtless

First recorded in 1585–95; thought 1 + -less

Explanation

When you're thoughtless about something, you don't spend much time thinking about what the consequences or effects on others might be. Smashing your neighbor's Jack-o-lantern was a thoughtless impulse you immediately regretted. If you've ever said, "I didn't really think about it hurting someone's feelings—I just did it," you've acted in a thoughtless way. This adjective is always at least a little bit negative, basically the opposite of thoughtful. It's thoughtless to invite everyone except the new kid at school to your birthday party, and it's thoughtless to throw trash on the ground instead of in a trash can. It's always better to stop and think first!

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Vocabulary lists containing thoughtless

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Her volition and intention don’t matter because an artist who is in on the joke makes hating less fun for the thoughtless critic.

From Salon • Jan. 10, 2026

Showed courage in the first innings to put a first-Test pair behind him and looked good in the second until a thoughtless shot.

From BBC • Dec. 7, 2025

A well-chosen pair of socks isn’t a thoughtless gift.

From The Wall Street Journal • Nov. 28, 2025

Am I wrong to think they are thoughtless?

From MarketWatch • Nov. 3, 2025

Newborn, preschool children, and music: Undesirable consequences of thoughtless neglect.

From "Music and the Child" by Natalie Sarrazin

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