The name Mithras (Latin, equivalent to Greek "Μίθρας",) is a form of Mithra, the name of an Iranian god, a point acknowledged by Mithras scholars since the days of Franz Cumont. The Greek form of the name appears in Xenophon's biography of Cyrus, the Cyropaedia, a work written in the fourth century BC. The word Mithra occurs as the name of a praiseworthy being in the Zoroastrian text, the Zend Avesta. Similar deity names in related Indo-european languages include Mitra, "मित्रः" found in Rig Vedic hymns. In Sanskrit, "mitra" means "friend" or "friendship".