Holy Orders

Holy Orders is the sacrament through which the mission entrusted by Christ to his apostles continues to be exercised in the Church until the end of time: thus it is the sacrament of apostolic ministry. It includes three degrees: episcopate, presbyterate, and diaconate
(Catechism of the Catholic Church 1536).

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Today the word "ordination" is reserved for the sacramental act which integrates a man into the order of bishops, presbyters, or deacons, and goes beyond a simple election, designation, delegation, or institution by the community, for it confers a gift of the Holy Spirit that permits the exercise of a "sacred power" (sacra potestas) which can come only from Christ himself through his Church
(Catechism of the Catholic Church 1538).
Ordination

Ordination is also called consecration, it is a setting apart and an investiture by Christ himself for his Church. the laying on of hands by the Bishop, with the consecratory prayer, constitutes the visible sign of this ordination
(Catechism of the Catholic Church 1538).