| ill-considered(careless, stupid, unthinking, obtuse, unperceptive) |
| impetuous(rash, oblivious, neglectful) |
| improvident(casual, happy-go-lucky, slapdash) |
| in the clouds |
| inaccurate(casual, happy-go-lucky, slapdash) |
| inane(careless, stupid, unthinking, obtuse, unperceptive) |
| incomprehensible(careless, stupid, unthinking, obtuse, unperceptive) |
| indiscriminating(obtuse, unperceptive) |
| indolent(casual, happy-go-lucky, slapdash) |
| inept(careless, stupid, unthinking, obtuse, unperceptive) |
| irrational(careless, stupid, unthinking, obtuse, unperceptive) |
| irresponsible(casual, happy-go-lucky, slapdash) |
| lackadaisical(casual, happy-go-lucky, slapdash) |
| lacking sight(expression, idiom) |
| lamebrained(careless, stupid, unthinking, obtuse, unperceptive) |
| lax(casual, happy-go-lucky, slapdash) |
| loony(careless, stupid, unthinking, obtuse, unperceptive) |
| loose(casual, happy-go-lucky, slapdash) |
| napping(casual, happy-go-lucky, slapdash) |
| nonchalant(casual, happy-go-lucky, slapdash) |