I've seen the word "dished" used to describe what I believe is a concavity in a screw hole that may very well indicate some kind of polishing beyond the factory. Am I picturing this correctly or am I completely off base? Does someone have a photo of a screw hole that is very obviously "dished" so I can look at that and see what that term actually means? I want to make sure when I read that word I know what it means and what I'm looking at.

Thanks!