See negligent in American Heritage Dictionary 4 Synonyms
negligent derelict lax neglectful remiss slack 1
These adjectives mean guilty of a lack of due care or concern: an accident caused by a negligent driver; was derelict in his civic responsibilities; lax in attending classes; neglectful of her own financial security; remiss of you not to pay your bill; slack in maintaining discipline.
See negligent in Webster's New World Roget's A-Z Thesaurus II
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