but given the recent lj_nifty thread here and that it took me and many others a while to realize the head links to the userinfo, I suggest that the word "head" be added before icon making:
... where "username" can be the username of any LiveJournal user. This is displayed as a bold link to the journal, with a head icon linking to the profile page (User Info).
And for communities it can say community icon. Sure community icon is non-descriptive and if you can describe that thingy, go for it. But given the comparison to head icon, I think most people will get it. And it least it will make it clear that communities and users get different icons.
Update: I just remembered, I think it was GFM who actually suggested "head" when I was using a more awkward wording. I intended to mention that originally - credit where credit is due, but I'm a little scatterbrained right now.