Take butterfly, for instance. It isn't really a fly. It isn't really butter. And it tastes icky (I'd like a second opinion though). Why did we name this insect after something it's not?
Or euthanasia. I thought to myself: "They're young. They're sexy. They're hip. They're Asian. What Chinese person doesn't look fondly on their euthanasia?" And then I found out what euthanasia was. So I changed my opinion of the matter.
Or buttermilk. It doesn't taste like butter or milk. I know this because I performed this experiment as a 9 year-old. I took milk and, well, Molly McButter because I somehow thought it work better than regular butter (powder dissolves better than solid butter does, as you may know). The result was, well, disappointing. And gagging. It was 10 years before I tried the real thing.
The same principle holds true for making orange julius from milk and powdered Tang. I learned the hard way.