«وفصاحة المتكلم: ملكة يقتدر بها على التعبير عن المقصود بكلام فصيح في أي غرض كان»
A speaker's eloquence is a developed capacity through which a person can express the intended meaning in eloquent speech, whatever the communicative purpose.
Four elements matter: an established capacity, ability to express, an intended meaning, and eloquent utterance. The definition describes an ability extending across communicative situations, not a single fortunate sentence.
Speaker-level eloquence is therefore a property of an individual’s capacity, whereas utterance-level eloquence judges the soundness of a particular expression.