Holy Thursday celebrates both the institution by Christ of the Eucharist and of the Holy Orders (the sacerdotal priesthood as distinct from the "priesthood of all believers").
The Sacrament of the Holy Orders includes bishops, priests and deacons. In the phrase "Holy Orders", the word "holy" means "set apart for some purpose." In this case the purpose is the ministry in the Body of Christ - the One, Holy and Apostolic Catholic Church.
Please pray for your priests and for new vocations to the priesthood.