I'm in college, and I'm still called the "Human Dictionary". Only the other day, I corrected a teacher who confused the words "archaic" [antiquated, outdated] and "arcane" [esoteric, obscure].
It's very easy to seem like you're rude or an elitist if you correct people too much, so I have refrained from doing it too often.
Oh...and if anyone has not heard of the board game "Balderdash", you should definitely try it out. It basically revolves around creating fictitious but seemingly appropriate definitions for some very obscure words. We used to play it in my middle school English classes, and it was seriously no competition for me. I actually got upset that my classmates didn't know what words like "apotheosis", "cromlech" and "malaise" meant.