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Reg·u·lus

(rĕgyə-ləs)

A bright binary star in the constellation Leo, approximately 78 light years from Earth.

[Latin rēgulus, diminutive of rēx, rēg-, king; see REGULUS.]

re·gu·lus

(rĕgyə-ləs)

n. pl. reg·u·li (-lī) or reg·u·lus·es

1. The metallic mass that sinks to the bottom of a furnace or crucible during smelting.

2. A relatively impure intermediate product of various ores in smelting.

[Latin rēgulus, diminutive of rēx, rēg-, king; see reg- in the Appendix of Indo-European roots.]

regu·line (rĕgyə-lĭn, -līn′) 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:

Indo-European Roots

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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