What is the "official" name of the -*- line?

[Ulrich Mueller]

Hi,

I've noticed that Emacs now outputs a message "Malformed mode-line"
when it encounters bad syntax in the first line of the file. [1]
This may be a little confusing because the line at the bottom of a
window is called mode line, too.

Anyway, this makes me wonder if there's an "official" name for that
line? In documentation and source code I've found all of the
following:

  `-*-' line
  first line
  mode-line
  prop line

Ulrich

[1] <http://bzr.savannah.gnu.org/lh/emacs/trunk/revision/105821>