What is Holy Orders?
Holy Orders in the Catholic Church include three orders: bishop, priest, and deacon. The Church regards ordination as a Sacrament. In the phrase “Holy Orders”, the word “holy” simply means “set apart for some purpose.” The word order (order, in Latin) designates an established civil body or corporation with a hierarchy, and ordination means legal incorporation into an order.
In context, therefore, a Holy Order is simply a group with a hierarchical structure that is set apart for ministry in the Church.