Wiki User
A WikiUser is a generic WikiRole:
The role name applies to anyone using a Wiki through its web-based user interface: WikiVisitor, WikiEditor or WikiAdmin. (Someone playing the role of WikiOwner or WikiMaster generally uses different user interfaces to interact with a Wiki application.)
Any of the following roles is a WikiUser:
In terms of classification, each of these would be a subclass of WikiUser.
See WikiRoles for other roles related to Wikis.