Mesolithic
WordNet
adjective
(1) Of or relating to a middle period of the Stone Age (following the paleolithic)
noun
(2) Middle part of the Stone Age beginning about 15,000 years ago
WiktionaryText
Etymology
From +
Adjective
- Of or referring to the Middle Stone Age (also the Mesolithic period or the Mesolithic age), a prehistoric period that lasted between 10,000 and 3,000 BC.