It can refer to any or all of those things, or anything else you want. A lot of times I hear of the "primary" being the person who you live with, have kids with, share expenses, etc. But it is not just that. Some people have more than one primary. "Secondary" doesn't necessarily mean "less important".
This is being discussed in a lot of elsewhere on this forum; I recommend using the search utility to find them, since it often pops up in the middle of a thread and is not always a part of the title.
Last edited by NeonKaos; 09-15-2009 at 11:25 PM.