Gross negligence is the "lack of slight diligence or care" or "a conscious, voluntary act or omission in reckless disregard of a legal duty and of the consequences to another party." In some jurisdictions a person injured as a result of gross negligence may be able to recover punitive damages from the person who caused the injury or loss.

Negligence is the opposite of diligence, or being careful. The standard of ordinary negligence is what conduct deviates from the proverbial "reasonable person". By extension, if somebody has been grossly negligent, that means they have fallen so far below the ordinary standard of care that one can expect, to warrant the label of being "gross". Gross negligence may thus be described as reflecting "the want of even slight or scant care", falling below the level of care that even a careless person would be expected to follow. While some jurisdictions equate the culpability of gross negligence with that of recklessness, most differentiate it from simple negligence in its degree.