from
The Collaborative International Dictionary of English v.0.48
Regulus \Reg"u*lus\ (-l?s), n.; pl. E. {Reguluses} (-?z), L.
{Reguli} (-l?). [L., a petty king, prince, dim. of rex,
regis, a king: cf. F. r['e]gule. See {Regal}.]
1. A petty king; a ruler of little power or consequence.
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2. (Chem. & Metal.) The button, globule, or mass of metal, in
a more or less impure state, which forms in the bottom of
the crucible in smelting and reduction of ores.
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Note: The name was introduced by the alchemists, and applied
by them in the first instance to antimony. It signifies
little king; and from the facility with which antimony
alloyed with gold, these empirical philosophers had
great hopes that this metal, antimony, would lead them
to the discovery of the philosopher's stone. --Ure.
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3. (Astron.) A star of the first magnitude in the
constellation Leo; -- called also the {Lion's Heart}.
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