Ameretat

() is the Avestan language name of the Zoroastrian divinity/divine concept of "not dying." As the hypostasis of immortality, Ameretat is the Amesha Spenta of long life on earth and perpetuality in the hereafter. Etymologically, Avestan ameretat derives from an Indo-Iranian root and is linguistically related to Vedic Sanskrit amṛtatva. The Indo-Iranian root has in turn Indo-European origins. In Common Era Zoroastrian tradition, Ameretat appears as Middle Persian Amurdad, continuing in New Persian as Mordad or Amordad.
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[Persian] One of the Amesha Spentas, Ameretat ("not dying", "living") is the personification of immortality and the protector of plants. The fifth month is dedicated to her. Her eternal opponent is the archdemon of ageing, Zarich.