What is "auscultare"

In regard to the reading of prayers with a graceful tone or accent, so to make an impression on the hearers, there was a person appointed, in monasteries, to hear the monks read, who instructed them how to perform it, before they were admitted to read publicly in the church, or before the people. This was called auscultare, q.d. to hear, listen.

"Quicunque Lecturus vel Cantaturus est aliquid in Monasterio; si necesse babeat ab eo, viz. Cantore, priusquam incipiat debet Auscultare." — Lanfranc in Decreta pro ordinis S. Benedicti.