What's the difference between an element that's "flown" and one that's "rigged"?

You'll often hear installation-and-dismantle professionals batting about these terms as they discuss suspended overhead exhibitry. While some people talk about "rigging," others refer to elements that are "flown." However, the terms are synonymous. That is, when structures such as headers, truss, light fixtures, etc. are attached to the ceiling of a venue, they are rigged, which is exactly the same as being flown.