1.  negligence(n = noun.act) carelessness, neglect, nonperformance - failure to act with the prudence that a reasonable person would exercise under the same circumstances;
is a kind of nonaccomplishment, nonachievement
has particulars: dereliction, comparative negligence, concurrent negligence, contributory negligence, criminal negligence, culpable negligence, neglect of duty, dodging, escape, evasion

2.  negligence(n = noun.attribute) neglect, neglectfulness - the trait of neglecting responsibilities and lacking concern;
is a kind of carelessness, sloppiness
has particulars: delinquency, dereliction, willful neglect, laxity, laxness, remissness, slackness
Derived form adjective negligent₁

1.  The quality or state of being negligent; lack of due diligence or care; omission of duty; habitual neglect; heedlessness. [1913 Webster]

2.  An act or instance of negligence or carelessness. [1913 Webster]
"remarking his beauties, . . . I must also point out his negligences and defects." [1913 Webster]

3.  The omission of the care usual under the circumstances, being convertible with the Roman culpa. A specialist is bound to higher skill and diligence in his specialty than one who is not a specialist, and liability for negligence varies acordingly. [1913 Webster]

negligence, n.
1 a a lack of proper care and attention; carelessness. b an act of carelessness.
2 Law = contributory negligence.
3 Art freedom from restraint or artificiality.

Derivative:
negligent adj. negligently adv.

Etymology:
ME f. OF negligence or L negligentia f. negligere = neglegere: see NEGLECT

N  neglect, carelessness, trifling, negligence, omission, oversight, laches, default, supineness, inattention, nonchalance, imprudence, recklessness, slovenliness improvidence, noncompletion, inexactness, paralipsis, paralepsis, paraleipsis (in rhetoric), trifler, waiter on Providence, Micawber, neglecting, unmindful, negligent, neglectful, heedless, careless, thoughtless, perfunctory, remiss, feebleness, inconsiderate, uncircumspect, incircumspect, off one's guard, unwary, unwatchful, unguarded, offhand, supine, inattentive, insouciant, imprudent, reckless, slovenly inexact, improvident, neglected, unheeded, uncared-for, unperceived, unseen, unobserved, unnoticed, unnoted, unmarked, unattended to, unthought of, unregarded, unremarked, unmissed, shunted, shelved, unexamined, unstudied, unsearched, unscanned, unweighed, unsifted, unexplored, abandoned, buried in a napkin, hid under a bushel, negligently, hand over head, anyhow, in an unguarded moment, per incuriam, Int, never mind, no matter, let it pass, out of sight, out of mind.

comparative negligence, concurrent negligence, contributory negligence, criminal negligence, culpable negligence