(I apologize that there have been similar questions before, but I'm not sure adding to them would be best here.  Perhaps the most reasonable option would be to add to [this question][1], but it is rather old, and adding stuff to the end of a long list will tend to bury it, which is the opposite of what I'm hoping to achieve here.)  

I have recently been perusing tags & questions & related materials, and I thought it might be worthwhile to try to bring some things to the community's attention.  It started when I edited [this question][2], which is tagged with both [tag:lme] and [tag:multilevel].  Neither of these tags has a wiki (excerpt or full), and they seem like synonyms to me.  I tried to map [multilevel] (which seems less used) to [lme], but the system wouldn't let me, as I don't have 5 upvotes on the tag.  So I thought I would raise the issue here, and if enough people agree, perhaps we can get this done somehow.  In addition, however, I notice that there are a few [pending synonyms][3] that don't seem to be getting any votes either way, so I thought I might as well list several options as answers below and let people vote on them to drive attention and action on this issue.  I would also like to encourage others who have additional suggestions to append them to this list (in that regard, note [this recent question][4], as well). 

  [1]: http://meta.stats.stackexchange.com/questions/120/tag-rename-suggestions
  [2]: http://stats.stackexchange.com/questions/29918/multilevel-covariance-structure-and-more
  [3]: http://stats.stackexchange.com/tags/synonyms
  [4]: http://meta.stats.stackexchange.com/questions/1198/should-the-data-visualization-and-figure-tags-be-merged