Hey Deacon!

The formal title of a priest is Reverend, but in common speech it is customary to address a priest simply as Father. Both titles describe what a priest is, but other titles more specifically address what a priest does.
 
The title of Pastor, which is Latin for “shepherd,” is given to a priest to whom a parish has been entrusted. It is the responsibility of the Pastor to teach, sanctify, and govern the parishioners entrusted to his care as he seeks to lead them to heaven. He does this under the authority of the Bishop and, sometimes with the assistance of other priests. The office of teaching includes work in Catholic schools, the Order of Christian Initiation of Adults, answering questions about the faith, etc. The office of sanctifying includes the administration of the Sacraments, as well as praying for the parishioners and helping them to pray. The office of governing includes the temporal affairs of the parish (insurance, payroll, physical plant, keeping the parish archive and the Sacramental records, etc.).
 
A priest whose task it is to assist a pastor is called Parochial Vicar, who in a certain sense, shares the voice of the pastor. “As co-workers with the pastor and sharers in his solicitude, they are to offer service in the pastoral ministry by common counsel and effort with the pastor and under his authority” (canon 545 § 1).
 
The title of Parochial Administrator is given a priest who takes care of a parish for a short time, usually until a pastor is appointed. The title is often given to a priest who is in his first parish leadership role prior to being installed as pastor.
 
The title of Very Reverend is given to the Vicar General (the bishop’s “second in command”), Judicial Vicars (the bishop’s chief canon lawyers), and Vicar Forane (or Dean).  The dean is the bishop’s representative within a diocesan territory called a “vicariate” or” deanery.” In our diocese there are seven deaneries. The dean helps coordinate the pastoral ministry within a deanery, provides support to his brother priests, and ensures proper administration is carried out. Priests retain these titles as long as they retain the office. 
 
The title Monsignor is an honorary title given to priests in certain positions within the diocese or the Roman Curia. There are three “grades” of monsignor. From “highest” to “lowest” they are: (1) Protonotary Apostolic, (2) Prelate of Honor, and (3) Chaplain of His Holiness. The rules on who can be named a monsignor were updated by Pope Francis in 2013. Only priests working within the Roman Curia or Vatican diplomatic service are eligible for all three “ranks.” Diocesan priests are only eligible for the third (lowest) of these honors and only after age 65.
 
The title of Rector is given to a priest to whom the care of a particular sacred building is entrusted, such as a Shrine or a Cathedral.
 
More than serving to establish a ranking among priests, these titles help to describe the sacred tasks entrusted to individual priests so that the work of the Church is more fruitfully carried out.
Author Bio:
 Deacon Dan Vaughn