This help page describes "disambiguation portals".
Disambiguation portals are peculiar to Wikiversity and reflect the unclear boundaries which exist between subjects at tertiary level, and the discontinuities which exist between subjects at primary, secondary and tertiary levels. Disambiguation portals focus less on the ambiguities of words and more on the ambiguities of the demarcations of entire fields of study. The general idea of a disambiguation portal is to avoid over-productive forking of portals and help users as quickly as possible to the most sensible portal possible for the subject they are seeking.
Examples: "Portal:English" is a title which could be claimed by a number of distinct subject areas (e.g. depending on whether the user is a native speaker or not). Portal:languages and Portal:natural sciences are examples of a superordinate term being too general to be helpful, so the respective disambiguation portals serve to redirect users to specific language portals and specific science portals.