MARMAR.  Latin.  Probably from Greek Marmaros (q.v.), meaning "to flash, shine, sparkle," which is akin to the Arabic Marmar, though some prefer to derive it from μάρναμαι ("to fight").  It is another name for Mars, the god of war.

... The Sabine words Marmar and Mamers (akin to μάρναμαι) are evidently names of the heaven-god. (The Encyclopaedia Britannica, v.15, 1888)

... The first element in Marusar or Maursar seems to be reduplicated in Marmares, the name of a Parthian king mentioned by Ctesias as contemporary with Astibaras king of the Medes (Spiegel: Erânisch. Alterth. II, p. 259); and again in Mermeroes, that of a Persian general of the time of Justinian (ibid. III, 412); while the second recurs in Manisares, the ruler of a part of Armenia and Mesopotamia in the time of Trajan (circ. 114 A.D.).  If we were dealing with Semitic terms, it would be natural to think of the Aramean mārē, "lord," in trying to explain the name before us.  Mari' was the name of a king of Damascus reduced by the Assyrian Rimmon-nirâri (circ. 804 B.C.). But a Semitic etymology being inappropriate, we may think of the widely-ramifying Aryan root MAR "to shine," "sparkle," "flash," and of the stem mâra, "brilliant," "illustrious," which Fick sees in the Gallic Indutio-marus, and the German Mâroald, Mârwin, Wolf-mâr, and the Slavonic Vladi-mîr; or of the root MAR "to pound," "crush," and the Greek μάρναμαι "to fight," and the Latin war-god Marmar, Mavors, Mars; or perhaps of the Greek μᾶυρο-ς (Hesych.) = μαρϜο-, in the sense of "gentle," "mild," (Ahd. maro, maraw-êr, Ags. mearu, mürbe, zart, schwach: Fick), and the Latin family-name Maro, and the Gallic chief Maro-boduus.  However this may be, the other half of the compound name Maresere or Māursara may obviously be explained by reference to the Zend çara, or sara, which means (1) head, (2) rule, (3) ruler according to Justi, and is identical with the Sanskr. çiras, Armen. çar (sar). (Proceedings of the Society of Biblical Archaeology, v.10, 1888)