Pliocene

Definition

Of a geologic epoch within the Neogene period from about 5.3 to 1.7 million years ago; marked by the appearance of humanity's first ancestors.

Etymology

From Ancient Greek πλείων (pleíōn, “more”) + καινός (kainós, “new”). Coined by English philosopher and historian of science William Whewell in 1831 for Charles Lyell, who introduced it in 1833 in his book Principles of Geology. By surface analysis, pleio- + -cene.

Example Sentences

• "[I]n a final sentence he expressed his conviction that his opponents "did not in truth represent the thought of the twentieth century, but might rather be regarded as mental fossils dug from some early Pliocene horizon "."