adj. Of, relating to, or being the period of geologic time from about 299 to 251 million years ago, the seventh and last period of the Paleozoic Era. The Permian Period is characterized by the formation of the supercontinent Pangaea, the first modern conifers, and the diversification of reptiles. It ended with the largest known mass extinction in the history of life. See Table at geologic time. n. The Permian Period. [After Perm Oblast, a region of west-central Russia.] |
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