Subdeacon (or sub-deacon) is a title used in various branches of Christianity.

Subdeacons in the Orthodox Church

A subdeacon or hypodeacon is the highest of the minor orders of clergy in the Orthodox Church. This order is higher than the reader and lower than the deacon.

Canonical Discipline

Like the reader, the clerical street-dress of the subdeacon is the cassock, which is usually black but only need be so if he is a monk. This is symbolic of his suppression of his own tastes, will, and desires, and his canonical obedience to God, his bishop, and the liturgical and canonical norms of the Church. As a concession in countries where Orthodoxy is little known, many only wear the cassock when attending services or when moving about the faithful on church business. In some jurisdictions in the United States, a clergy-shirt will sometimes be worn instead of a cassock, and is commonly worn buttoned but with no collar or collar-tab to indicate a rank lower than deacon.

There is a special service for the tonsuring of a subdeacon, although in contemporary practice an acolyte or a reader may receive the bishop's blessing to vest and act as a subdeacon generally or for a particular occasion if there is no subdeacon available. This situation often arises if there is a need for a subdeacon and a likely candidate has stated an intention to marry but has not yet done so, causing a delay in his ordination. The reason for this lies in the fact that the canons prohibit subdeacons to marry after their ordination (just like deacons and priests). This latter stipulation has led, in some places, to the reservation of the formal ordination service as a stepping-stone for candidates for the priesthood, although this is by no means universal. It also means that, while teenagers who show particular fervour may be ordained as acolytes and readers, the subdiaconate is usually reserved for those of more mature years; the canonical minimum age for subdiaconal ordination is twenty years.