- an indefinite and very long period of time；a unit of time equal to a thousand million years.
noun: aeon, plural noun: aeons
- 1. an indefinite and very long period of time he reached the crag aeons before I arrived
- ▪ a unit of time equal to a thousand million years.
- ▪ a major division of geological time, subdivided into eras the Precambrian aeon
- 2. (in Neoplatonism, Platonism, and Gnosticism) a power existing from eternity; an emanation or phase of the supreme deity.
- an indefinite and very long period of time, often a period exaggerated for humorous or ... he reached the crag eons before I arrived his eyes searched her face for what seemed like eons
Oxford American Dictionary