neg·li·gent 
(nĕglĭ-jənt)
(nĕglĭ-jənt)adj.
1. Given to or characterized by neglect, especially habitual neglect: The negligent worker missed another deadline.
2. Law Acting with or done through negligence.
[Middle English, from Old French, from Latin neglegēns, neglegent-, present participle of neglegere, to neglect; see NEGLECT.]
negli·gent·ly adv.
Synonyms: negligent, derelict, lax, neglectful, remiss, slack1
These adjectives mean guilty of a lack of due care or concern: The negligent landlord failed to repair the window. By not voting, he was derelict in his civic duty. If you're lax in attending class, your grades will suffer. Many neighbors felt that he had been neglectful of his property. It was remiss of her not to call to tell us she was coming. The teacher was slack in maintaining discipline.
These adjectives mean guilty of a lack of due care or concern: The negligent landlord failed to repair the window. By not voting, he was derelict in his civic duty. If you're lax in attending class, your grades will suffer. Many neighbors felt that he had been neglectful of his property. It was remiss of her not to call to tell us she was coming. The teacher was slack in maintaining discipline.