Mar ( **', written with a silent final yodh; ), also **Mor''' in Western Syriac, is an Aramaic word meaning "lord". The corresponding feminine forms in Syriac are Morth and Marth for "lady" (, ). It is a title of reverence in Syriac Christianity, where the title is placed before the Christian name, as in Mar Aprem / Mor Afrem for Ephrem the Syrian, and Marth / Morth Maryam for St Mary. It is given to all saints and is also used in instead of "Most Reverend", just before the name in religion taken by bishops. The title of Moran Mor / Maran Mar is given to the Catholicoi and other primates; and the title Mar / Mor is given to prelates such as metropolitan bishops or archbishops.

In Christianity

The variant Moran or Maran (, ), meaning "Our Lord", is a particular title given to Jesus, either alone or in combination with other names and titles. Likewise, Marth or Morth (, , "Our Lady") is a title of Mary, mother of Jesus. Occasionally, the term Maran or Moran has been used by various Eastern Christian patriarchs and catholicoi, who started using it in the recent centuries. The Syriac Orthodox Patriarch of Antioch, the Jacobite Syrian Catholicos titles are called Moran Mor, while the Malankara Orthodox Catholicos use the title Moran Mor. Sometimes the Indian bearers of this title are called Moran Mar, using a hybrid style from both Syriac dialects that reflects somewhat the history of Syro-Malabar Christians. The Pope is referred to as Marpāpa (Holy Father) by the St Thomas Christians of India. The variant Marya or Moryo (, ) is the original form of Mara/Moro, but only used in reference to God in the circle of Syriac Christianity. This word is used in the Peshitta Old Testament to render the Tetragrammaton. Although Mara/Moro is clearly a derived form of the above Marya/Moryo, and ultimately has roots in common Semitic, there is a fanciful derivation found in early Syriac lexica, that the word is an initialism as follows:

In Judaism

In Mishnaic Hebrew through to date, this Aramaic word is pronounced [mar], and it is used as a formal way of addressing or referring to a male person. In the Talmud, Tabyomi is sometimes referred to as Mar. "Mar" was also the honorific of the Exilarch (leader of the Jewish diaspora community in Babylon), with the Aramaic-speaking Jews sharing many cultural attributes with the Syriac Christians. In the Modern Hebrew of contemporary Israel, "Mar" is used without distinction for any male person, like "Mr." in English. However, in Rabbanical circles of Jews from the Middle East, the Aramaic variant form מָרָן (Maran, Aramaic: our lord) is still a title used for highly appreciated Rabbis, such as Ovadia Yosef, the spiritual leader of the Shas party.

In Mandaeism

In Mandaeism, names for Hayyi Rabbi ("the Great Life") in Mandaic (an Eastern Aramaic variety) include the cognate word Mara as in ࡌࡀࡓࡀ ࡖࡓࡀࡁࡅࡕࡀ ('Lord of Greatness' or 'The Great Lord'; see also the Manichaean term Father of Greatness).