A woman officially charged with certain functions in the Church. St. Paul speaks of Phoebe as one who ministered to the church at Cenchrae (Romans 16:1), but the term "deaconess" did not come into use until the fourth century.
Gradually the office developed and was recognized by the Church. Among other duties a deaconess devoted herself to the care of the sick and the poor of her sex; she was present at interviews of women with bishops, priests, or deacons; instructed women catechumens and kept order in the women's part of a church. Her most important function was at the baptism of women, where she assisted the deacons. But as adult baptisms declined, deaconesses became less prominent. The decline was accelerated by the abuses that crept in where deaconesses arrogated to themselves ministerial functions, e.g., among the Monophysites and Nestorians, where they administered Holy Communion, read the Scriptures, and preached. Several regional council abrogated the office, which was never a formal ordination, but deaconesses were found in the West until the eleventh century. In the East, where the privileges of deaconesses were more pronounced, including investiture with the state and distribution of the chalice, the decline was slower.
In Protestantism deaconesses date from the nineteenth century. And among the Anglicans they are admitted by the episcopal imposition of hands conferring lifelong status.