Somebody with special talent in various activities.
You have to be an artdax to debate Hillary Clinton because she is very articulate and slick.
Someone who has profound knowledge of many different subjects and topics.
Rush Limbaugh tries hard to be an artdax, but he falls miserably short.
An erudite individual or sage.
When George Bush and John Kerry debated, they tried to sound artdaxly to gain audience approval and ultimately to gain votes.
A legend in his own mind. A self proclaimed master.
If that artdax was a fraction as smart as he thinks he is, he'd be winning millions on Jeopardy.