The quality or state of being blurred; the condition of lacking clarity or sharp focus.
From 'blurred' plus the abstract noun suffix '-ness,' which creates nouns from adjectives. This is a formal, less common variant of 'blurriness.'
Both 'blurredness' and 'blurriness' mean the same thing, but 'blurriness' wins in real speech—this shows how English speakers prefer '-iness' to '-edness' for abstract qualities.
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