(TheNewYorkTimes) - I NEVER like to try your patience, but please bear with me as we delve into a knotty gray area of wine terminology. The notion in question is structure, along with several related terms, like shape, focus, precision and definition. These are by no means big words, and they don’t convey complicated ideas. I use them a lot without thinking much about them. Yet when I tried to look up these terms in reference books, I could find very little.