A double monastery is an institution combining a separate monastery

Monastery

Monastery denotes the building, or complex of buildings, that houses a room reserved for prayer as well as the domestic quarters and workplace of monastics, whether monks or nuns, and whether living in community or alone .Monasteries may vary greatly in size – a small dwelling accommodating only...

 for monk

Monk

A monk is a person who practices religious asceticism, living either alone or with any number of monks, while always maintaining some degree of physical separation from those not sharing the same purpose...

s and an abbey

Abbey

An abbey is a Catholic monastery or convent, under the authority of an Abbot or an Abbess, who serves as the spiritual father or mother of the community.The term can also refer to an establishment which has long ceased to function as an abbey,...

 for nun

Nun

A nun is a woman who has taken vows committing her to live a spiritual life. She may be an ascetic who voluntarily chooses to leave mainstream society and live her life in prayer and contemplation in a monastery or convent...

s. Examples include Coldingham Monastery in Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

, and Einsiedeln Abbey

Einsiedeln Abbey

Einsiedeln Abbey is a Benedictine monastery in the town of Einsiedeln in the Canton of Schwyz, Switzerland. The abbey is dedicated to Our Lady of the Hermits, the title being derived from the circumstances of its foundation, from which the name Einsiedeln is also said to have originated...

 and Fahr Abbey

Fahr Abbey

Fahr Abbey, is a Benedictine nunnery located in Würenlos in the Canton of Aargau, Switzerland. Situated in different cantons, Einsiedeln Abbey and the convent in Fahr are a double monastery, controlled by the abbot of Einsiedeln.- Geographical and administratively special situation :In fact, the...

 in Switzerland, controlled by the abbot

Abbot

The word abbot, meaning father, is a title given to the head of a monastery in various traditions, including Christianity. The office may also be given as an honorary title to a clergyman who is not actually the head of a monastery...

 of Einsiedeln. Whilst the monks and nuns lived in separate buildings they were usually united in the Abbess as head of the entire household and would have chanted the Liturgy of the Hours

Liturgy of the hours

The Liturgy of the Hours or Divine Office is the official set of daily prayers prescribed by the Catholic Church to be recited at the canonical hours by the clergy, religious orders, and laity. The Liturgy of the Hours consists primarily of psalms supplemented by hymns and readings...

 and attended Mass

Mass

Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...

 together in the Chapel. Either an abbess

Abbess

An abbess is the female superior, or mother superior, of a community of nuns, often an abbey....

 or an abbot

Abbot

The word abbot, meaning father, is a title given to the head of a monastery in various traditions, including Christianity. The office may also be given as an honorary title to a clergyman who is not actually the head of a monastery...

 would normally have control over both houses, and it was only in exceptional circumstances that each would have its own superior. Double monasteries were common in Ireland

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

 and Anglo-Saxon England during the early medieval period.

Double monasteries were forbidden by the Second Council of Nicaea

Second Council of Nicaea

The Second Council of Nicaea is regarded as the Seventh Ecumenical Council by Roman Catholics, Eastern Orthodox, Eastern Catholic Churches and various other Western Christian groups...

 in 787, though it took many years for the decree to be enforced. During the Middle Ages

Middle Ages

The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...

, in fact, a number of religious houses were established on this pattern, both among Benedictine

Benedictine

Benedictine refers to the spirituality and consecrated life in accordance with the Rule of St Benedict, written by Benedict of Nursia in the sixth century for the cenobitic communities he founded in central Italy. The most notable of these is Monte Cassino, the first monastery founded by Benedict...

s and possibly the Dominicans. The Bridgittines were consciously founded using this form of community.

Less frequently, the term is used to describe one monastery based on two sites like the Monkwearmouth-Jarrow Priory.