reg·​u·​lus ˈre-gyə-ləs How to pronounce regulus (audio)
capitalized : a first-magnitude star in the constellation Leo
[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 examples are programmatically compiled from various online sources to illustrate current usage of the word 'regulus.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

First Known Use

1559, in the meaning defined at sense 1

Time Traveler
The first known use of regulus was in 1559

Dictionary Entries Near regulus

Cite this Entry

“Regulus.” Dictionary, Merriam-Webster, Accessed 14 Jul. 2024.

Biographical Definition


biographical name

Reg·​u·​lus ˈre-gyə-ləs How to pronounce Regulus (audio)
Marcus Atilius died circa 250 b.c. Roman general

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