Palaeolithic

/ˌpælɪəʊˈlɪθɪk/
noun
1.
the period of the emergence of primitive man and the manufacture of unpolished chipped stone tools, about 2.5 million to 3 million years ago until about 12 000 bc. See also Lower Palaeolithic, Middle Palaeolithic, Upper Palaeolithic
adjective
2.
(sometimes not capital) of or relating to this period