What is of, pertaining to, or designating, certain strata which occupy an intermediate position between the Eocene and Miocene periods. -- n. The Oligocene period. See the Chart of Geology called?

oligocene — Of, pertaining to, or designating, certain strata which occupy an intermediate position between the Eocene and Miocene periods. -- n. The Oligocene period. See the Chart of Geology. (Webster's 1913.)

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