name that (partial) chord: 5-6-6+ in DAd

This is not a game, but a genuine question. I am working on an arrangement of "Londonderry Air" ("Danny Boy") in a DAd tuning, and in one spot use a 5-6-6+ chord.  It sounds appropriate, but I have no idea what it is. The notes involved are B, G, and C#.

It comes on "hushed" as in "Or when the valley's hushed and white with snow."  I am using a 5-5-7 Bm chord on "val" and then a single 6+ on the melody for "ley" and then I have this 5-6-6+ chord for "hushed."  It sounds good, and I have no existential need to name it, but I am creating tab for my local dulcimer group and I'm putting chords above the standard music notation.

Any idea what chord or partial chord that might be?