I. Why Is This Sacrament Called “Orders”?

From The Catechism of the Catholic Church

1538
Integration into one of these bodies in the Church was accomplished by a rite
called ordinatio, a religious and liturgical act which was a consecration, a
blessing or a sacrament. 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)⁵ which can come only from Christ himself through his Church.
Ordination is also called consecratio, for 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.

PART TWO: THE CELEBRATION OF THE CHRISTIAN MYSTERY

SECTION TWO THE SEVEN SACRAMENTS OF THE CHURCH
- CHAPTER THREE THE SACRAMENTS AT THE SERVICE OF COMMUNION
  - ARTICLE 6 THE SACRAMENT OF HOLY ORDERS
    - I. Why Is This Sacrament Called “Orders”?

From The Catechism of the Catholic Church – rosary.team