reg·​u·​lus | \ ˈre-gyə-ləs How to pronounce regulus (audio) \

Definition of regulus

1 capitalized : a first-magnitude star in the constellation Leo
2 [Medieval Latin, metallic antimony, from Latin] : the more or less impure mass of metal formed beneath the slag in smelting and reducing ores

Examples of regulus in a Sentence

Recent Examples on the Web Regulus will be only three degrees away from the moon, about equal to the width of your two middle fingers held at arm’s length. National Geographic, 4 July 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'regulus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of regulus

1559, in the meaning defined at sense 1

History and Etymology for regulus

New Latin, from Latin, petty king, from reg-, rex king — more at royal

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The first known use of regulus was in 1559

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Cite this Entry

“Regulus.” Dictionary, Merriam-Webster, Accessed 24 May. 2022.

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Regulus biographical name

Reg·​u·​lus | \ ˈre-gyə-ləs How to pronounce Regulus (audio) \

Definition of Regulus

Marcus Atilius died circa 250 b.c. Roman general

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