The quality or state of being culpable; deserving of blame or responsibility.
From culpable + -ness (suffix creating nouns from adjectives meaning 'the quality of'). This noun form allows culpability to be discussed as an abstract quality.
The existence of both 'culpability' and 'culpableness' shows how English loves synonyms—both words mean the same thing, but 'culpableness' is rarely used because 'culpability' became the standard formal choice.
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