This is my honorific, coined back in 1969 and occasionally used by others, for the individual who excels at more than one nonadjacent art or, more precisely, is a master of several unrelated arts. The principal qualifier in my definition isnonadjacent.
In my understanding (sometimes missed by others using the term), painting and sculpture are adjacent, as are both film and photography, and both poetry and fiction (as many individuals excel at each pair). However, poetry and music are not...