Frashokereti (𐬟𐬭𐬀𐬴𐬋⸱𐬐𐬆𐬭𐬆𐬙𐬌 frašō.kərəti) is the Avestan language term (corresponding to Middle Persian 𐭯𐭫𐭱(𐭠)𐭪𐭥𐭲 fraš(a)gird ) for the Zoroastrian doctrine of a final renovation of the universe, when evil will be destroyed, and everything else will be then in perfect unity with God (Ahura Mazda).
The doctrinal premises are (1) good will eventually prevail over evil; (2) creation was initially perfectly good, but was subsequently corrupted by evil; (3) the world will ultimately be restored to the perfection it had at the time of creation; (4) the "salvation for the individual depended on the sum of [that person's] thoughts, words and deeds, and there could be no intervention, whether compassionate or capricious, by any divine being to alter this." Thus, each human bears the responsibility for the fate of his own soul, and simultaneously shares in the responsibility for the fate of the world.
The name suggests "making wonderful, excellent". D. N. MacKenzie in A Concise Dictionary of Pahlavi gives the meaning as "the Restoration (at the end of time)". Considering this meaning, the first part could indicate "early, first, initial", related to fra prefix, cognate with pro in Greek and Latin. Then the overall meaning being "making into initial state", hence "restoration".
The eschatological ideas are only alluded to in the surviving texts of the Avesta, and are known of in detail only from the texts of Zoroastrian tradition, in particular in the ca. 9th-century Bundahishn. The accompanying story, as it appears in the Bundahishn (GBd 30.1ff), runs as follows: At the end of the "third time" (the first being the age of creation, the second of mixture, and the third of separation), there will be a great battle between the forces of good (the yazatas) and those of evil (the daevas) in which the good will triumph. On earth, the Saoshyant will bring about a resurrection of the dead in the bodies they had before they died. This is followed by a last judgment through ordeal.