Astronomy. Regulus, a first magnitude star in the constellation Leo.
Metallurgy.
the metallic mass that forms beneath the slag at the bottom of the crucible or furnace in smelting ores.
an impure intermediate product obtained in smelting ores.
First recorded in 1550–60; from 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
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
It is not clear from Agricola's account whether the test with nitric acid was applied to the regulus or to the "lumps".
From De Re Metallica, Translated from the First Latin Edition of 1556 by Agricola, Georgius
Agricola describes the separation of the silver from the regulus by preliminary melting with argols, glass-gall, and some lead, and subsequent cupellation of the lead-silver alloy.
From De Re Metallica, Translated from the First Latin Edition of 1556 by Agricola, Georgius
A regulus is a compound of one or more of the metals with sulphur; it is usually brittle, often crystalline, and of a dull somewhat greasy lustre.
From A Text-book of Assaying: For the Use of Those Connected with Mines. by Beringer, Cornelius
What is commonly called arsenic is the calx of a semi-metal called the regulus of arsenic.
From Heads of Lectures on a Course of Experimental Philosophy: Particularly Including Chemistry by Priestley, Joseph
A chemical compound so called from its power of dissolving gold. regulus of cobalt: early chemical term referring to the metallic mass of an ore.
From The Short-story by Atkinson, William Patterson
Some standouts: Regulus Therapeutics went up 120%; 89bio went up 85%; Chimerix gained 69% and Intra-Cellular Therapies rose 57%.
From MarketWatch ● Nov. 3, 2025
Regulus Therapeutics works on therapies that target what’s called microRNA, a type of molecule that helps control the function of cells.
From Los Angeles Times ● May 2, 2025
Find the Plough and trace a line down from the two stars on the right until you find Regulus, the brightest star in the constellation of Leo.
From BBC ● Nov. 17, 2024
“I would like to see the gaming industry hire more gay people and give them the tools in order to better reflect our lived experiences,” Regulus said.
From New York Times ● Feb. 13, 2024
“Why? Where did it come from? What did Regulus have to do with it? Kreacher, sit up and tell me everything you know about that locket, and everything Regulus had to do with it!”
From "Harry Potter and the Deathly Hallows" by J.K. Rowling
The Vulgate has it, "in caverna reguli;" which, however, is not classic Latin.
From The Grammar of English Grammars by Brown, Goold
These ealdermen, or earls, were honoured with titles of reguli subreguli, principes, patricii, and some times rex.
From The Mirror of Literature, Amusement, and Instruction Volume 13, No. 357, February 21, 1829 by Various
Mr. Ray himself had no knowledge of this bird, but received his account from Mr. Johnson, who apparently confounds it with the reguli non cristati, from which it is very distinct.
From The Natural History of Selborne, Vol. 1 by Morley, Henry
Mr. Ray himself had no knowledge of this bird, but received his account from Mr. Johnson, who apparently confounds it with the reguli non cristati, from which it is very distinct.
From The Natural History of Selborne by White, Gilbert
In the middle of the ninth century, Harold Harfager, one of the reguli of Norway, subdued the other petty rulers, and made himself king of the whole country.
From Notes and Queries, Number 182, April 23, 1853 A Medium of Inter-communication for Literary Men, Artists, Antiquaries, Genealogists, etc. by Bell, George
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