Alas these are mostly neologisms created by combining roots from classical languages. That's a recipe for creating new "obscure" words pretty much on demand. The best sort of obscure words are ones that are obscure because they're old or highly specialized, not because someone made them up and they never really became part of the spoken language.
Here's another cool list, very similar; the standard on this list is, "words so interesting that David Foster Wallace circled them in his dictionary":<p><a href="http://www.slate.com/id/2250784" rel="nofollow">http://www.slate.com/id/2250784</a><p>(Teaser: conchoidal, corvee, demulcent, exergue, gramnvirous, etc etc etc).
Beware, some definitions here are incorrect.<p>For example, Witzelsucht, which is correctly defined at Wikipedia. <a href="http://en.wikipedia.org/wiki/Witzelsucht" rel="nofollow">http://en.wikipedia.org/wiki/Witzelsucht</a><p>For people interested, Phonistry maintains some much nicer (longer, etc.) lists. <a href="http://phrontistery.info/w.html" rel="nofollow">http://phrontistery.info/w.html</a>
Unrelated: What is the point in publishing an interesting list such as this and then restricting my ability to highlight so I can copy and paste? (Chrome 4.1 on Windows)
This reminds me of that board game (I forget the name) in which some silly definition is read and the players have to make up words and convince their opponents (who are guessing which word matches the definition) that their word is correct. With some of these words, I feel like I'm playing that game and someone is trying to trick me. I mean, zenzizenzizenzic is a number raised to the eighth power? Seriously? But it exists! <a href="http://en.wikipedia.org/wiki/Zenzizenzizenzic" rel="nofollow">http://en.wikipedia.org/wiki/Zenzizenzizenzic</a>
Next time I need a put-down for someone's argument, I think I might call it "jumentous," which according to this page means "[s]melling like horse urine."
Reminded me of Douglas Adams and John Lloyd (creator of QI)'s <i>The Meaning of Liff</i>:<p><a href="http://folk.uio.no/alied/TMoL.html" rel="nofollow">http://folk.uio.no/alied/TMoL.html</a>