Pleis ‧ to ‧ cene /ˈplaɪstəsiːn/ BrE AmE adjective
[ Date: 1800-1900 ; Language: Greek ; Origin: pleistos 'most' + kainos 'recent' ]
belonging to the period in the Earth’s history that started about two million years ago and ended about 10,000 years ago, when much of the Earth was covered with ice