Any of various armored ornithiscian dinosaurs of the group Thyreophora from the Jurassic and Cretaceous Periods, bearing bony plates or spikes, and including the ankylosaurians and the stegosaurians.
[New Latin Thyreophora, taxon name, Greek thureos, oblong shield; see THYROID + Greek -phora, neuter pl. of -phoros, -phore.]
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Indo-European & Semitic Roots Appendices
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