All three Greek words denote causal powers that are beyond the reach of human control, and hence were often personified as goddesses.

The word "moira" means a share, part, or portion, and by derivation, the fate allotted to a person. In mythological contexts, it was personified either as a single goddess or, as in Hesiod's Theogony and in the myth of Plato's Republic X, as a group of three goddesses (Clotho, Lachesis, Atropos). Moira or the Moirai determine the fate of individuals by "spinning" the thread of one's life. The word "moira" sometimes euphemistically refers to death, as the fate of all humans. In other contexts it refers to one's rank or distinction or to the positive abilities allotted by the gods, such as poetic inspiration. In Stoic determinism, it is used in relation to universal fate (heimarmenē).

The noun...