Concept
αἰών · aiōn
Aiōn (αἰών) means an age, a lifetime, and, at its height, eternity. It first named the vital span or life-force of a living being; philosophy raised it to mean the timeless mode of being that belongs to what is fully real. It survives in our 'aeon', a vast stretch of time.
The word's most famous moment comes in Plato's Timaeus. When the Demiurge fashions the cosmos, the eternal model cannot be perfectly copied in a changing world; so the god makes, in place of the changeless life of eternity, 'a moving image of eternity' that proceeds according to number — and this image we call time. The wheeling of the heavens is eternity counted out, the nearest that becoming can come to the abiding now of true being.
Later Platonists made aiōn the very life of the intelligible world — not endless clock-time but a whole that possesses all its being at once, without before or after, in a single standing present. To rise from time toward eternity, from the scattered succession of moments toward that gathered fullness, is one more image of the soul's ascent toward its source.
PLATO SCROLL