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thyr·e·oph·o·ran

(thîr′ē-ŏfə-rən)

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.]

thyr′e·opho·ran adj.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

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Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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