Well, this should help explain. Here is a pdf document compiled by SJSU's own Jeremy Kemp on the use of Second Life as a teaching tool. Second Life (wikipedia) is a virtual world that is on the Internet. The term Metaversity is a hack of the word Metaverse and University. According to Wikipedia, "The Metaverse, a phrase coined by Neal Stephenson's science fiction novel Snow Crash (1992) constitutes Stephenson's vision of how a virtual reality-based Internet might evolve in the near future." In my opinion this virtual reality-based Internet will be Web 3.0.
They may be college teachers and students, but they're also pioneers — exploring strange new worlds that exist nowhere on Earth. That's because their classes and field trips take place only on computers, using an online digital world called Second Life. - USAToday