Sean Nós - song, sung in the "old style". It's a traditional form of singing from Ireland. A capalla, for sure, with much vocal decoration.
And yet, and yet... There's an old flavor to Sinéad O'Connor's interpretation of the songs, some of which I remember from my childhood ("I'll tell me Ma" and "Báidín Fheilimí" - I'm looking at you two). We'd sing them in the car as, as a family, we went on drives through the Wicklow countryside south of Dublin.
And so, a "new" take on the "old style". Sean Nós - Nua.