n. (pl. reguluses or reguli) Chem.
1. the purer or metallic part of a mineral that separates by sinking on reduction.
2 an impure metallic product formed during the smelting of various ores.
Derivatives:
reguline adj.
Etymology: L, dimin. of rex regis king: orig. of a metallic form of antimony, so called because of its readiness to combine with gold