Grokking grok
Here's a shock: young people don't grok grok.
One young science fiction geek used it in a presentation in class last night and it turn out that the only other person in the room who had ever heard the word was yours truly. Yeah, I first heard it in my SF years, too, but I thought it had been sufficiently popularized by hippies and hackers to be in the general lexicon.
Especially in Austin, where BookPeople began its life as the tiny Grok Books over on 17th Street. But now I'm really dating myself.