n. Any of various carnivorous pelycosaurs of the genus Dimetrodon of the Permian Period, having long spines on the back that supported a sail-like structure, and powerful jaws with sharp teeth. [New Latin Dimetrodōn, genus name : Greek di-, two; see DI-1 + Greek metron, measure; see mē-2 in the Appendix of Indo-European roots + Greek odōn, tooth (from its having two different kinds of teeth); see dent- in the Appendix of Indo-European roots.] |
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