Catechism of the Catholic Church
“The inexhaustible richness of this sacrament is expressed in the different names we give it. Each name evokes certain aspects of it. It is called: The Lord’s Supper, because of its connection with the supper which the Lord took with his disciples on the eve of his Passion and because it anticipates the wedding feast of the Lamb in the heavenly Jerusalem.”
Source: Catechism of the Catholic Church #1328-9