In this discussion, I haven't seen any practical alternatives to the use of the word "grid" as a generic name for a grid-based virtual environment.
The word "standalone" only makes sense to people who have configured OpenSim .INI files, which the majority of OpenSim users aren't going to do, and writing "grids, mini-grids and standalones" all the time is cumbersome and unwieldy.
I like the idea of using "virtual world" to denote those grids that are large, with active communities, like InWorldz and Avination. But I can see how that can be confusing, since "virtual world" is commonly used to refer to many non-OpenSim virtual worlds as well.
I tend to use "social grids" or "commercial grids" to distinguish those grids from business, school and personal grids.