14 minutes ago, mgaretz said:
ETA: It does not have anything to do with the wine country. According to Wikipedia: The word "napa" in the name napa cabbage comes from colloquial and regional Japanese, where nappa (菜っ葉) refers to the leaves of any vegetable, especially when used as food.
Yes, I was just about to edit to mention that, but you beat me to it. By the way. Wikipedia articles on the various Brassica rapas are all over the place, self contradictory and utterly confusing. But that bit is correct.