Magic user

'Magic user is a non-defined user of magic.

Background
While the term can apply to all magic users, as a term defined as essentially as 'practioner of magic' (in a similar way that 'magician' is sometimes used as a generic description for all magic users).

However, it can often can apply to magic users who do not fall into more specific types of magic users (and as such it might be considered a non-profesional practioner of magic).