NEGLECTFUL

derelict, delinquent, neglectful, remiss

(adjective) failing in what duty requires; “derelict (or delinquent) in his duty”; “neglectful of his duties”; “remiss of you not to pay your bills”

inattentive, neglectful

(adjective) not showing due care or attention; “inattentive students”; “an inattentive babysitter”; “neglectful parents”

Source: WordNet® 3.1

Etymology

Adjective

neglectful (comparative more neglectful, superlative most neglectful)

Tending to neglect; failing to take care of matters which require attention.

Source: Wiktionary

Neg*lect"ful, a.

Definition: Full of neglect; heedless; careless; negligent; inattentive; indifferent. Pope. A cold and neglectful countenance. Locke. Though the Romans had no great genius for trade, yet they were not entirely neglectful of it. Arbuthnot.

– Neg*lect"ful*ly, adv.

– Neg*lect"ful*ness, n.

Source: Webster’s Unabridged Dictionary 1913 Edition