I use at least two modes of speaking to people. In one, I have a well-thought-out idea in mind, and I want to share the idea; I can answer all sorts of detailed questions about it because I understand it, and my agenda is to explain it. The other mode is more fuzzy and hand-wavy. I'm giving the impression of an idea, drawing loose connections, and saying that I see something there. The first mode is comparable to painting a photorealistic image, while the other is comparable to painting an impressionistic image. I'd like a word for the impressionistic version. I often say things like "just brainstorming", or "in a hand-wavy way". For example, I think this post is somewhat hand-wavy. Usually I feel the need to surround this stuff with disclaimers, and that takes time -- I think it's useful sometimes to say hand-wavy stuff, and I think people could do it more easily if they could bracket it with a word.