negligent; inadvertent; to act without sufficient care or attention

to be unwary or careless; lacking in vigilance or caution

to be neglectful and careless; oversight or negligence

to lose a critical position or suffer a major defeat because of negligence. This idiom refers to the historical event where the general [[关羽|關羽|guan1 yu3]] lost [[荆州|荊州|jing1 zhou1]] to his rivals during the Three Kingdoms period.