In everyday conversation, when we refer to an event that happens "after" something else, we use the Latin prefix, "post." "Meta" sounds more exotic, but it's just its Greek counterpart. However, the Hellenic prefix is slightly more nuanced, as it also means "about." Metacinema, for example, is a technique thanks to which directors can create movies "about" cinema itself. Fellini's 8 ½ or Truffaut's La Nuit Américaine are perfect examples of this practice. Meta-search engines? Same concept: search engines that search on other search engines. That's what "meta" ultimately means. So, when defining a meta-universe (a meta-verse), we have to consider both connotations of the term: a universe "beyond" the one we currently inhabit and one that's also self-referral.