The blog of trogool has a useful delineation of the different ways “open” is used wrt Open Source, Open Standards, Open Access and more. The post points out that the open-access movement exhausts itself contending with the
same old misunderstandings over and over again.

To help fix that problem, the post offers a “brief, simplistic guide to
several flavors of open,” organized around the following questions:

• What is the target of this movement? What is
  being made open? As compared to what?
• What legal regimes are implicated?
• How does openness happen? What are the major
  variants of open works of this type?

http://scienceblogs.com/bookoftrogool/2010/03/battle_of_the_opens.php