The quality or state of being especial; the fact of being outstanding, distinctive, or particularly important.
From especial + -ness, a productive English suffix creating abstract nouns from adjectives. The compound formation follows standard English morphology dating back centuries.
Adding -ness to adjectives is such a simple English trick that kids naturally do it—we can turn almost any descriptor into a noun, creating words like 'especialness' that might not be in the dictionary but everyone understands!
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