designating or of the first geologic epoch of the Neogene, characterized by the joining of what are now Africa, Arabia, and Eurasia and the development of manlike apes
< Gr meiōn, less (see minor) + -cene
See Miocene in American Heritage Dictionary 4
Of or belonging to the geologic time, rock series, or sedimentary deposits of the fourth epoch of the Tertiary Period, characterized by the development of grasses and grazing mammals. See Table at geologic time.
The Miocene Epoch or its system of deposits.
Origin: Greek meiōn, less; see mei-2 in Indo-European roots