remiss

Synonyms: any old way any which way asleep at switch asleep on job behindhand culpable daydreaming defaultant delinquent derelict dilatory disregardful fainéant forgetful heedless inattentive indifferent indolent lackadaisical lax lazy neglectful negligent regardless slack slapdash slipshod sloppy slothful slow tardy uninterested unmindful woolgathering

Antonyms: careful mindful scrupulous thorough thoughtful