thoughtless

[thawt-lis] /ˈθɔt lɪs/
adjective
1.
lacking in consideration for others; inconsiderate; tactless:
a thoughtless remark.
2.
characterized by or showing lack of thought:
a shallow, thoughtless book.
3.
not thinking enough; careless or heedless:
thoughtless of his health.
4.
devoid of or lacking capacity for thought.
Origin
1585-95; thought1 + -less
Related forms
thoughtlessly, adverb
thoughtlessness, noun
Synonyms
1. negligent, neglectful. 3. inattentive, remiss.
Examples from the web for thoughtless
  • Most home fi res are due to careless or thoughtless behavior, and are easily preventable.
  • The act or behavior may be thoughtless or something you did not mean to do.
British Dictionary definitions for thoughtless

thoughtless

/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
Derived Forms
thoughtlessly, adverb
thoughtlessness, noun
Word Origin and History for thoughtless
adj.

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