The quality or state of being baneful; the degree to which something is harmful or destructive.
From baneful (harmful or poisonous) + -ness suffix, forming an abstract noun. Traces back through baneful to Old English bana meaning 'destroyer.'
Philosophers in the 18th century used 'banefulness' to describe the moral corruption of society—it's a word that sounds heavy because it was coined to carry intellectual weight about abstract harms.
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