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definitions

thoughtless

[thawt-lis]
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SEE MORE SYNONYMS FOR thoughtless ON THESAURUS.COM

adjective

lacking in consideration for others; inconsiderate; tactless: a thoughtless remark.
characterized by or showing lack of thought: a shallow, thoughtless book.
not thinking enough; careless or heedless: thoughtless of his health.
devoid of or lacking capacity for thought.

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RELATED WORDS

inconsiderateness, negligence, carelessness, inattention, oversight, disregard, neglect

Origin of thoughtless

First recorded in 1585–95; thought1 + -less
Related formsthought·less·ly, adverbthought·less·ness, noun

Synonyms for thoughtless

SEE MORE SYNONYMS FOR thoughtless ON THESAURUS.COM
1. negligent, neglectful. 3. inattentive, remiss.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for thoughtlessness

Contemporary Examples of thoughtlessness

Historical Examples of thoughtlessness

British Dictionary definitions for thoughtlessness

thoughtless

adjective

inconsideratea thoughtless remark
having or showing lack of thoughta thoughtless essay
unable to think; not having the power of thought
Derived Formsthoughtlessly, adverbthoughtlessness, noun
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
Word Origin and History for thoughtlessness

thoughtless

adj.

"inconsiderate," 1794, from thought + -less. Related: Thoughtlessly; thoughtlessness.

Online Etymology Dictionary, © 2010 Douglas Harper