A person who participates in or conducts colloquies; someone skilled at formal conversation or dialogue.
From colloquium (Latin col- 'together' + loqui 'to speak') + -ist (one who practices or is skilled in). A relatively rare term appearing mainly in academic and historical contexts.
Colloquists were basically the medieval equivalent of today's debate team champions or podcast hosts—people who could have sophisticated conversations in front of audiences. The fact that we don't really use this word anymore says something about how we've democratized intellectual conversation.
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