Paleo

from the Greek roots: palaio, palai, palaio

"Paleo" is a term that is most often used as a prefix meaning "old" or "ancient". For example, paleogeography (ancient landscapes) or paleontology (ancient life). In the context of The Paleo Diet, it is more specifically referring to the "Paleolithic Era", also called the "Old Stone Age", from about 2.5 million years ago until about 10,000 years ago.