PLEISTOCENE

(Geology) Of, belonging to, or designating the geologic time, rock series, and sedimentary deposits of the earlier of the two epochs of the Quaternary Period, characterized by the alternate appearance and recession of northern glaciation and the appearance of the progenitors of human beings. Also commonly referred to as the Ice Age, a period which immediately preceded the Holocene epoch, or about from 2 million years ago to 10,000 years ago.