Passagio

          —from the Italian:  passage; passing;
          a crossing/the transition between vocal registers

Every singer finds that rift in their voice,
let’s say B for you, D-flat for me, that refuses
breath passage, forced to a rasp. You have to find a way
to get where you’re going as if nothing difficult is going on.

In Purcell’s song “The Blessed Virgin’s Expostulation” 
Mary discovers the adolescent Jesus has disappeared
to who knows where in the Temple,
her anxiety too large for her heart to hold.