This should match the docstring for Coord.name() (as supplied by CFVariableMixin.name()), taking into account how the name() method is being called. In other words:
 - It should mention the var_name attribute.
 - The "default name" will actually be the literal value "unknown".
 - It should probably use attribute names instead of the English equivalents. For example, "standard_name" instead of "standard name".
 - Probably it should link to the Coord.name() documentation. (NB. This link won't work right now because that method isn't showing up in the documentation. Once *that* is fixed, perhaps most of the detail for this argument could be removed and we just rely on the link.)