The quality or state of being angelic; the characteristic of resembling or acting like an angel.
From 'angelic' plus the suffix '-ness' (forming abstract nouns from adjectives), a straightforward English word formation pattern.
We have both 'angelicalness' and 'angelicness'—different suffixes creating the same meaning—and both are rare now, showing how English often creates multiple forms but standardizes to just one.
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