Whereas when played separately it would be an referred to as an arpeggio. But in harmony we might still refer to it as a chord, as in saying, arpeggiate the C# minor (chord) to start moonlight sonata.

This might better be described as arpeggiating C#m second inversion or even C#m/G# in the right over C# in the left...

This is getting possibly-weird but you could call it an arpeggiation of G#sus4(#5)/C#