I don't know whether there's a generally accepted definition; the sailing definition seems reasonable, though.
Here's a more general definition I though of that might do: it allows more paths than the sailing one, yet still prevents short walks around the pole:
"A circular path is a circumnavigation if you cannot cut the globe exactly in half so that the path lies entirely inside one of the halves."
Carroll Morgan
Slashdot Mirror
I don't know whether there's a generally accepted definition; the sailing definition seems reasonable, though. Here's a more general definition I though of that might do: it allows more paths than the sailing one, yet still prevents short walks around the pole: "A circular path is a circumnavigation if you cannot cut the globe exactly in half so that the path lies entirely inside one of the halves." Carroll Morgan