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Webster 1828 Edition

inadvertence ‎(countable and uncountable, plural inadvertences)

The state or quality of being inadvertent; inadvertency; heedlessness; carelessness; negligence.

Many mistakes proceed from inadvertence.

Inadvertency, or want of attendance to the sense and intention of our prayers. — Jeremy Taylor.
An effect or result of inattention; an oversight or mistake from negligence.