Uncommon Term for an Excellent Orator?
Solution 1:
If you want something very unusual and yet historically resonant, you might try chrysostomic (that is, "golden-mouthed"). Here's the OED definition of that word:
Chrysostomic a. rare. {f. Gr χρυσοστομος golden-mouthed, an epithet applied to favourite orators which became a kind of surname of Dio and John Chrysostom.} Golden-mouthed.
[Example:] 1816 Month[ly] Rev[iew] LXXXI 245 By the majesty of his Chrysostomic eloquence.
The quotation from The Monthy Review (November 1816) runs at greater length as follows:
Dean Williams, also, with the plasticity of a Roman cardinal, after having subdued by his arguments the puritan chieftain Dr. Reynolds, stalked into the see of Lincoln, which he disdained to illustrate, but, changing his career, took up the seals which Bacon had laid down, and attracted the admiration of the House of Lords by a probity more unfaultering, by a profounder knowlege of the civil law, and by the majesty of his Chrysostomic eloquence.
Wikipedia has fairly detailed articles on both Dio Chrysostom and (Saint) John Chrysostom.
The OED also has an entry for chrysostomatical, which has essentially the same meaning as chrysostomic but (to me) doesn't sound as good.
Solution 2:
Silver-tongued
A tendency to be eloquent and persuasive in speaking.
Solution 3:
Ciceronian :
- in the style of Cicero: characterized by melodious language, clarity, and forcefulness of presentation: Ciceronian invective.
a Cicero:
- Roman statesman, orator, and philosopher. A major figure in the last years of the Republic, he is best known for his orations against Catiline and for his mastery of Latin prose. His later writings introduced Greek philosophy to Rome. (TFD)
- ... Adam Smith were particular admirers, but perhaps there was no more devoted Ciceronian, as to both literary style and ideas, than Edmund Burke, whose thought has been called "a Cicero filtered through the Christian scholastic tradition.