| oblivious(adjective, careless, indifferent, silly, foolish) |
| offhand(adjective, careless, indifferent, casual, thoughtless) |
| regardless(adjective, careless, indifferent, foolish, stupid) |
| tactless(adjective, careless, thoughtless, unkind, insensitive) |
| vacuous(adjective, careless, indifferent, stupid, blank) |
| accustomed(adjective, natural, instinctive, automatic, inherent) |
| blank(adjective, thoughtless) |
| congenital(adjective, natural, instinctive, automatic, inherent) |
| empty-headed(adjective, slight, careless, indifferent, foolish) |
| ill-advised(adjective, dull, careless, foolish, stupid) |
| inane(adjective, dull, slight, careless, indifferent) |
| inborn(adjective, natural, instinctive, automatic, inherent) |
| indifferent(adjective, sharp, rude, careless, short) |
| ingrained(adjective, natural, instinctive, automatic, inherent) |
| intrinsic(adjective, natural, instinctive, automatic, inherent) |
| intuitional(adjective, natural, instinctive, automatic, inherent) |
| intuitive(adjective, natural, emotional, instinctive, automatic) |
| lightweight |
| mad(adjective, foolish, unreasonable, illogical) |
| moronic(adjective, dull, simple, slow, silly) |