n. pl. ru·bies
1. A red, translucent variety of the mineral corundum, highly valued as a precious stone.
2. Something, such as a watch bearing, that is made from a ruby.
3. A dark or deep red to deep purplish red.
Of the color ruby.
[Middle English, from Old French rubi, from Medieval Latin rubīnus (lapis), red (stone), ruby, from Latin rubeus, red; see reudh- in the Appendix of Indo-European roots.]
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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:
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.