The quality of being friendly, likeable, and easy to get along with.
From Latin 'amicabilis' (friendly), derived from 'amicus' (friend). The '-ability' suffix converted the adjective into a noun describing the quality itself.
Amiability might be one of those words that's actually worth using because it perfectly captures that feeling when someone is just genuinely nice—not fake-nice, but actually easy to be around in every situation.
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