What does "inattention" mean?

Inattention: Want of attention, or failure to pay attention; disregard; heedlessness; neglect. Novel lays attract our ravished ears; But old, the mind inattention hears. Pope. -- Inattention, Inadvertence. We miss seeing a thing through inadvertence when do not happen to look at it; through inattention when we give no heed to it, though directly before us. The latter is therefore the worse. Inadvertence may be an involuntary accident; inattention is culpable neglect. A versatile mind is often inadvertent; a careless or stupid one is inattentive.