Polymath: Discovery and Definition

In reading (sort of re-reading, more on that later) Natasha by David Bezmozgis, I stumbled across an unfamiliar word:

polymath

It's not that I have an extraordinarily large vocabulary, but I'm a good reader so there are few words that don't surrender their meaning through context clues.

My uncle was a good man, a hard worker, and a polymath. He read books, newspapers, and travel brochures, He could speak with equal authority about the Crimean War and the Toronto Maple Leafs. Short months after arriving in Toronto he took a job giving tours of the city to visiting Russians. But he wasn't rich and never would be.

A polymath is obviously a smart person. Poly means many, so based on all the things the uncle can do, it could mean that he's multi-talented, or interested in many things. I could stop there, but I'm interested in the other root; the "math" part of the word.

 So apparently, the Greek word that gave us mathematics really mean to learn. So our polymath is many-learned (that's learn-ED, stress on the second syllable).