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tri·lo·bite

(trīlə-bīt′)

Any of numerous extinct marine arthropods of the class Trilobita, of the Paleozoic Era, having a segmented body divided by grooves into three longitudinal lobes and found as fossils throughout the world.

[New Latin Trilobītēs, former class name, from Greek trilobos, three-lobed : tri-, tri- + lobos, lobe.]

tri′lo·bitic (-bĭtĭk) adj.

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trilobite

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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