The quality or state of being well-mannered, courteous, or possessing social grace and propriety.
From Old French 'bien' (well) + -ness (English suffix forming abstract nouns), though this word is archaic and rarely used in modern English.
This word perfectly captures the old French obsession with politeness (from which we get words like 'bienséance')—yet it vanished from English, replaced by simpler words like 'courtesy' and 'grace'.
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