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Synonyms for Thoughtless (same or very similar meaning)

WordNet sense 1 (not exhibiting or characterized by careful thought):
unthinking, unreflective, unthoughtful

WordNet sense 2 (without proper consideration or reflection):

WordNet sense 3 ((usually followed by `to') unwilling or refusing to pay heed):

WordNet sense 4 ((usually followed by `of') without due thought or consideration):
careless, regardless

WordNet sense 5 (marked by or paying little heed or attention):
heedless, unheeding

WordNet sense 6 (without care or thought for others):

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