What Alteration between a cantor chanting Psalm verses and a choir singing a refrain is called?

The alteration between a cantor chanting Psalm verses and a choir singing a refrain is called "responsorial psalmody." In this practice, the cantor leads with verses from the Psalm, and the congregation or choir responds with a repeated refrain, creating a call-and-response dynamic that enhances participation and reflection in the liturgical setting.