This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. Marked by or showing lack of due thought or care; careless. See Synonyms at careless.

adj. Inconsiderate; inattentive: a thoughtless remark.

adj. Lacking thought: The debate turned into thoughtless bickering.

adj. Marked by or showing lack of due thought or care; careless.

adj. Inconsiderate, inattentive.

adj. Lacking thought or consideration.

ad. Lacking thought; careless; inconsiderate; rash.

ad. Giddy; gay; dissipated.

ad. Deficient in reasoning power; stupid; dull.

Devoid of or lacking capacity for thought.

Unthinking; heedless; careless; giddy.

Synonyms Heedless, Remiss, etc. (see negligent), regardless, inattentive, inconsiderate, unmindful, flighty, harebrained.

adj. without care or thought for others

adj. showing lack of careful thought

"There is never a need to deny the harm that ignorance can cause, and use of the term thoughtless usually refers to some action taken without thoughtful consideration."

inconsiderate    unconsidered    unthinking    unthoughtful    unreflective   

blank    careless    stupid   

careless    inconsiderate    rash    giddy    gay    dissipated    stupid    dull   

foolish    frivolous    heartless    irresponsible    childish    heedless    insolent    sinful    impulsive    wanton