The word Moirai, also spelled Moirae or Mœræ,[3][4] comes from Ancient Greek: μοῖρα, which means "lots, destinies, apportioners".

[5] The possible derived Latin meritum, "reward", English merit, maybe coming from the Proto-Indo-European language root *(s)mer, "to allot, assign".

This derives from Roman mythology, in which they are the Parcae or Fata, plural of Latin: fatum,[11] meaning prophetic declaration, oracle, or destiny; euphemistically, the "sparing ones".

In Norse mythology the Norns are a trio of female beings who rule the destiny of gods and men, twining the thread of life.

[14] In younger legendary sagas, the Norns appear to have been synonymous with witches (völvas), and they arrive at the birth of the hero to shape his destiny.

[16] In Lithuanian and other Baltic mythologies, the goddess Laima is the personification of destiny, and her most important duty was to prophesy how the life of a newborn will take place.

In Dante's Divine Comedy, the Fates are mentioned in both Inferno (XXXIII.126) and Purgatorio (XXI.25-27, XXV.79-81) by their Greek names, and their traditional role in measuring out and determining the length of human life is assumed by the narrator.

[20] Hecate, the chthonic Greek goddess associated with magic, witchcraft, necromancy, and three-way crossroads,[21] appears as the master of the Three Witches.

[24] In the Avestan religion and Zoroastrianism, aša, is commonly summarized in accord with its contextual implications of "truth", "righteousness", "order".

Aša and its Vedic equivalent, Rta, are both derived from a PIE root meaning "properly joined, right, true".

[26] In the literature of the Mandaeans, an angelic being (Abatur) has the responsibility of weighing the souls of the deceased to determine their worthiness, using a set of scales.

[30] The individuals fulfill their true natures when they follow the path set for them by the ordinances of Rta, acting according to the Dharma, which is related to social and moral spheres.

The word is the proper name of the divinity Maat, who was the goddess of harmony, justice, and truth represented as a young woman.

[33] Maat was the norm and basic values that formed the backdrop for the application of justice that had to be carried out in the spirit of truth and fairness.

In the famous scene of the Egyptian Book of the Dead, Anubis, using a scale, weighs the sins of a man's heart against the feather of truth, which represents maat.

He calls them to send their sisters, the Hours Eunomia ("lawfulness"), Dike ("right"), and Eirene ("peace"), to stop the internal civil strife.

[43] Another important Mycenaean philosophy stressed the subjugation of all events or actions to destiny and the acceptance of the inevitability of the natural order of things; today this is known as fatalism.

Eventually, the concept of one's destined portion in life began to be personified as a spirit or daemon, referred to as Aisa or Moira, who would determine the appropriate time for one's death at the moment of their birth.

[48] The three Moirai are daughters of the primeval goddess Nyx ("night"), and sisters of Keres ("the black fates"), Thanatos ("death"), and Nemesis ("retribution").

[49] In the cosmogony of Alcman (7th century BC), first came Thetis ("disposer, creation"), and then simultaneously Poros ("path") and Tekmor ("end post, ordinance").

"[57] In the Homeric poems Moira or Aisa are related to the limit and end of life, and Zeus appears as the guider of destiny.

[63] The Erinyes, a group of chthonic goddesses of vengeance, served as tools of the Moirai, inflicting punishment for evil deeds, particularly upon those who sought to avoid their rightful destiny.

[70][71] A similar scenario is depicted on a Mycenaean vase, where Zeus holds a scale in front of two warriors, indicating that he is measuring their destiny before the battle.

[74] The Pythian priestess at Delphi once admitted that Zeus was also subject to their power, though no recorded classical writing clarifies to what exact extent the lives of immortals were affected by the whims of the Fates.

Simonides names this power Ananke (necessity) (the mother of the Moirai in Orphic cosmogony) and says that even the gods don't fight against it.

[84] On Korkyra, the shrine of Apollo, which according to legend was founded by Medea was also a place where offerings were made to the Moirai and the nymphs.