Adjective
1. showing lack of careful thought;
"the debate turned into thoughtless bickering"2. marked by or paying little heed or attention;
"We have always known that heedless self-interest was bad morals; we know now that it is bad economics"--Franklin D. Roosevelt"heedless of danger""heedless of the child's crying"3. without care or thought for others;
"the thoughtless saying of a great princess on being informed that the people had no bread; `Let them eat cake'"4. (usually followed by `of') without due thought or consideration;
"careless of the consequences""the proverbial grasshopper--thoughtless of tomorrow""crushing the blooms with regardless tread"