I took it to mean that the geek character in the movie was deliberately dumbing things down for the person he was explaining to, out of disdain for their positi

I took it to mean that the geek character in the movie was deliberately dumbing things down for the person he was explaining to, out of disdain for their position. He was basically saying, "This is the most valuable substance in the universe, and we can only get it here" in as bluntly and impossible-to-misunderstand way as he could. It wasn't in the context of "Quick, pass me that bar of unobtanium!", or other in-universe common-usage (a la "midichlorians"), but rather a deliberate simplification. ("What do we mine here? __important shit__! Now leave me alone and go back to your useless sociology experiment while I do something important!")