Presbyterian refers to our form of church government. A "presbyterian" church is simply a church that is governed by a group of "presbyters" or elders. This group of elders is made up of the pastor(s) of the church and scripturally qualified men who are elected by the congregation.
Traditionally a reformed church is one that holds to the "solas" of the Reformation:
The authority of Scripture: sola scriptura (Scripture alone)
The basis of salvation: Sola Gratia (Grace alone)
The means of salvation: Sola Fide (Faith alone)
The merit of salvation: Solus Christus (Christ alone)
The goal of salvation: Sola Deo Gloria (God's glory alone)