Logomacy
Between logomachy and logomancy . . .

Of course, the tool this came from gives no indication whatsoever of what method it uses to determine readability, and sneakily inserts a link to an advertiser in the html they give you to copy, so caveat lector.

Update: After Googling around a little, my guess is that the tool uses the Flesch-Kincaid Grade Level readability test, both because it delivers the results in categories that roughly correspond to grade level, and because it’s a test that’s simple enough to calculate with a tiny program.  The formula (from the Wikipedia article) is:

 

It’s my infatuation with sesquipedalian verbiage I tells ya.