Epiclesis
CCC
"At the heart of the Eucharistic celebration are the bread and wine that, by the words of Christ and the invocation of the Holy Spirit, become Christ's Body and Blood" (CCC #1333).
Roman Canon (Eucharistic Prayer I)
Be pleased, O God, we pray,
to bless, acknowledge,
and approve this offering in every respect;
make it spiritual and acceptable,
so that it may become for us
the Body and Blood of Your most beloved Son,
Our Lord Jesus Christ.
References