The quality or state of being bonair; graciousness, courtesy, or refined manner.
Derived from 'bonair' plus the noun-forming suffix '-ness', which comes from Old English and creates abstract nouns representing qualities or states.
'-ness' is the most prolific suffix in English, turning almost any adjective into its abstract quality—bonairness is a perfect example of how medieval writers could invent new words to discuss virtue and character.
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