does #document mean "document" or "#document"?

The DOM spec (both level 1 and the level 2 candidate) specifies that the Node
interface has a "nodeName" attribute; the spec has a table showing the value of
the "nodeName" attribute (and other attributes) for each node type.  The table
row for the Document node type looks like this:

Document    #document   null    null

Now, just what does "#document" mean?  Does it mean a string consisting of the #
character followed by the word "document"?  Or is the # some sort of notation
indicating a literal string, so that the string itself contains only the word
"document"?  This is really pretty unclear.  I searched the spec for an
explanation of the  "#" character, but couldn't find one.

-adam