> And uncommon words are much easier to understand, given a dictionary, than common words are. The fact that they're uncommon means they don't have the wide variety of meanings and usages.

A somewhat related phenomenon is that many fancy words in European languages have Latin or Greek roots, so foreign language speakers can correlate with a similar word in their own language, or, for those of us who wasted some of our youth on this, may even be familiar with the word in the original language.