The Orthodox Church has no specific 'job titles' so to speak, though specific members of the Heirarchy will have specific titles according to their means. Here are some key examples and Explanations of terms.
Within the Eastern Orthodox Church there are 9 Patriarchs, with 6 Autocephalous Metropolitans who were granted Autocephaly over their various territories by the Patriarchates. Neither of these answer to a higher authority except for The Archbishop of Athens whose territories are partially under Constantinople.
There are six further Autonomous Archbishops/Metropolitans who have regional control over their territories, these were granted their Autonomy through one of the larger Churches and therefore cannot take the title of Patriarch as their head is appointed through another Patriarch.
(List Of Eastern Orthodox Heirarchs Here)
As well as this, within the Non-Chalcedonian Tradition there are 6 Oriental Orthodox Patriarchs/Catholicoi, with 4 Titular Patriarchs (and Catholicoi) holding Authority over specific areas but recognizing the Spiritual Authority of their Patriarch overall. The Oriental Orthodox community and Eastern Orthodox are not in communion, due to the Chalcedonian Schism of 451, though each retains its structure, with some cases of dual Patriarchs in the same place (Alexandria, Antioch, Istanbul/Constantinople, Jerusalem)
(List of Non-Chalcedonian Heirarchs Here)
(List of Non-Chalcedonian Heirarchs Here)
Each Patriarch has authority over his Patriarchate, with no interference of others, though to make major decisions he would need the support of his Synod (Bishops in his Juristiction) and in many cases is expected to have support from the other Patriarchs, which is why the Orthodox Church does not have the changes in Doctrine in the way that other communities may.
Titles for heads of Jurisdictions
The head of a specific community will generally be called a Patriarch, Pope or Catholicos.
Patriarch is the most common title for the leader of an Orthodox Community.
The term Pope originates in Egypt in the Patristic era and has been continued to be used by the Coptic Community rather than Patriarch. The Official Title of the Greek Orthodox Patriarch of Alexandria is also "Pope and Patriarch of Alexandria and all Africa" though he is commonly simply called Patriarch.
Catholicos means 'Of the Whole' and is used by the Georgian Church in the Eastern Tradition and Armenian and Malankara (Indian/Jacobite) Churches in the Oriental Traditions
Titles for Bishops
Within each Jurisdiction there are Bishops heading Dioceses or with an Administrative role. They will have Titles based upon their role and authority
Metropolitan Bishop/Archbishop was the highest Authority until the title Patriarch was created at Nicaea in 325. These Bishops can rank above or below Archbishops depending on the Tradition (Macedonia and Serbia hold Archbishops as higher, most others rank Archbishops lower). They have no specific power or direct authority over other Bishops, though have the right to oversee Synods and Councils due to their higher authority in the Church itself.
Bishop is the title given to the head of Diocese. The title dates from Apostolic times and is present in the writings of St paul, as well as St ignarius the Apostolic, who stated that all must be done through the Bishop. a Bishop is traditionally a male monastic (Since the 6th Century) or Celibate Priest, who has a role over an administrative function or Diocese. until recent times, these were only Diocesan and could not be transferred between Dioceses (By the Nicene Canons they were seen as 'Married' to one) though in recent years in the Eastern Orthodox Church this has changed. A Bishop without a Diocese is called a 'Titular Bishop' in the Eastern Orthodox and 'General Bishop' in the Coptic Orthodox Church.
The Synod is the group of meetings. Since Orthodoxy keeps its Conciliar Structure, they play a vital role in discussing issues regarding the jurisdiction.
By the Canons of Chalcedon, every Patriarchate must hold a 6 Monthly Synod meeting, this was later changed to yearly at Trullo. This is also existent in the Oriental Orthodox Church who only recognise the first three Ecumenical Councils as being truly Ecumenical. The Synodial meetings will often be attended by all Bishops in that Patriarchate, who will discuss issues as a whole with the Patriarch residing, also holding separate meetings in specific councils, regarding different matters which will be reported to the Synod as a whole after. Dioceses also hold yearly Synodial meetings to discuss matters within that Diocese.