The quality of being dappled; having a pattern of spots or patches of color or light and shade.
From 'dapple' plus the abstract noun suffix '-ness'; a variant construction to describe the state of being dappled.
Both dappledness and dappleness exist as possible English words, showing that our language doesn't always have one 'correct' way to make abstract nouns—it's flexible enough to generate multiple valid forms.
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