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regulus

[ reg-yuh-luhs ]
/ ˈrɛg yə ləs /
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noun, plural reg·u·lus·es, reg·u·li [reg-yuh-lahy]. /ˈrɛg yəˌlaɪ/.
(initial capital letter)Astronomy. a first magnitude star in the constellation Leo.
Metallurgy.
  1. the metallic mass that forms beneath the slag at the bottom of the crucible or furnace in smelting ores.
  2. an impure intermediate product obtained in smelting ores.
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Origin of regulus

1550–60; <Latin rēgulus literally, little king (diminutive of rēx); in early chemistry, antimony, so called because it readily combines with gold (the king of metals); see -ule

Other definitions for regulus (2 of 2)

Regulus
[ reg-yuh-luhs ]
/ ˈrɛg yə ləs /

noun
Marcus A·til·i·us [uh-til-ee-uhs], /əˈtɪl i əs/, died 250? b.c., Roman general.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use regulus in a sentence

British Dictionary definitions for regulus (1 of 3)

regulus
/ (ˈrɛɡjʊləs) /

noun plural -luses or -li (-ˌlaɪ)
impure metal forming beneath the slag during the smelting of ores

Derived forms of regulus

reguline, adjective

Word Origin for regulus

C16: from Latin: a petty king, from rēx king; formerly used for antimony, because it combines readily with gold, thought of as the king of metals

British Dictionary definitions for regulus (2 of 3)

Regulus1
/ (ˈrɛɡjʊləs) /

noun
Marcus Atilius (ˈmɑːkəs əˈtɪlɪəs). died ?250 bc, Roman general; consul (267; 256). Captured by the Carthaginians in the First Punic War, he was sent to Rome on parole to deliver the enemy's peace terms, advised the Senate to refuse them, and was tortured to death on his return to Carthage

British Dictionary definitions for regulus (3 of 3)

Regulus2
/ (ˈrɛɡjʊləs) /

noun
the brightest star in the constellation Leo. Visual magnitude: 1.3; spectral type: B8; distance: 69 light years
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for regulus

Regulus
[ rĕgyə-ləs ]

A bright triple star in the constellation Leo, with an apparent magnitude of 1.35. Scientific name: Alpha Leonis.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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