Palaeolithic
/ˌpælɪəʊˈlɪθɪk/( <美> Paleolithic)
adjective
1- Archaeology of, relating to, or denoting the early phase of the Stone Age, lasting about 2.5 million years, when primitive stone implements were used【考古】（与）旧石器时代（有关）的。
The Palaeolithic period extends from the first appearance of artefacts to the end of the last ice age （about 8, 500 years ago）. The period has been divided into the Lower Palaeolithic, with the earliest forms of humankind and the emergence of hand-axe industries （ending about 120, 000 years ago）, the Middle Palaeolithic, the era of Neanderthal man （ending about 35, 000 years ago）, and the Upper Palaeolithic, during which only modern Homo sapiens is known to have existed.
词源
mid 19th cent.: from PALAEO- 'of prehistoric times' + Greek lithos 'stone' + -IC .