Inadvertence (noun)

1. Lack of attention or care; lack of vigilance or caution.
2. Lack of intention or purpose; an unintentional act or omission.

Origin:

Late 16th century: from french inadresse or latin inadvenientia, from inadvenire "to come upon unawares", from in- "not" + advenire "to arrive".

Examples:

1. His mistake was due to an inadvertence.
2. The company"s failure was a result of the CEO"s inadvertence.
3. The accident was caused by the driver's inadvertence.
4. The writer's mistake was an inadvertence, not a lack of research.
5. The injury was caused by an advertence.