plainsong

He appears familiar with the plainsong, and has based a symphony and portions of a quartet on Gregorian modes.

And Winchester, too, has all and more than all, the surprise of the plainsong; the better you know it the more you are impressed.

Descant in music is the melodious accompaniment to a simple theme, the plainsong or ground.

There was a chapel in the house, of a High Anglican kind, where vestments and incense were used, and plainsong sung.

Florid music, or all church music that is not Plainsong, or its Lutheran equivalent the chorale-melody.