The quality or state of being coequal; equivalence in rank or standing.
From coequal + -ness (Old English suffix forming abstract nouns), an alternative nominalization to coequality.
While 'coequality' sounds more formal and Latin-derived, 'coequalness' has an older English feel—it's the kind of philosophical term a Renaissance thinker might use to describe the 'coequalness' of a husband and wife in marriage.
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