The Collaborative International Dictionary of English v.0.48:

Paleolithic \Pa`le*o*lith"ic\ (p[=a]`l[-e]*[-o]*l[i^]th"[i^]k),
   a. (Geol.)
   Of or pertaining to an era marked by early stone implements.
   The Paleolithic era (as proposed by Lubbock) includes the
   earlier half of the "Stone Age;" the remains belonging to it
   are for the most part of extinct animals, with relics of
   human beings.
   [1913 Webster]

WordNet (r) 3.0 (2006):

paleolithic
    adj 1: of or relating to the second period of the Stone Age
           (following the eolithic); "paleolithic artifacts" [syn:
           paleolithic, palaeolithic]
    n 1: second part of the Stone Age beginning about 750,00 to
         500,000 years BC and lasting until the end of the last ice
         age about 8,500 years BC [syn: Paleolithic Age,
         Paleolithic, Palaeolithic]