Arcturus

American  

[ahrk-toor-uhs, -tyoor-] / ɑrkˈtʊər əs, -ˈtyʊər- /

noun

Astronomy.

1. a first-magnitude star in the constellation Boötes.

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Arcturus British  

/ ɑːkˈtjʊərəs /

noun

1. the brightest star in the constellation Boötes: a red giant. Visual magnitude: –0.4; spectral type: K2III; distance: 37 light years

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Arcturus Scientific  

/ ärk-tr′əs /

1. A giant star in the constellation Boötes. It is the brightest star in the Northern Hemisphere and the fourth brightest star in the sky, with an apparent magnitude of 0.00. Scientific name: Alpha Boötes.

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Other Word Forms

• Arcturian adjective

Etymology

Origin of Arcturus

1352–75; < Latin < Greek Arktoûros, equivalent to árkt ( os ) bear + -oûros keeper; replacing Middle English arture < Middle French

Example Sentences

To find the area of sky where it should appear, she advises to first locate the plough and follow its handle to Arcturus.

From BBC • Dec. 30, 2024

XBB.1.16, nicknamed Arcturus, has fallen to second place, and is estimated to comprise 15.6% of specimens.

From Los Angeles Times • Aug. 10, 2023

Meanwhile, Arcturus has jumped to around 12.5 percent of cases, a rise from just 1 percent at the end of March.

From Salon • May 16, 2023

The World Health Organization has categorized Arcturus as a “variant of interest,” which means it has genetic changes that could affect its behavior, along with an advantage over other variants in circulation.

From Scientific American • May 12, 2023

The actual velocity of Arcturus is probably still greater.

From Astronomical Curiosities Facts and Fallacies by Gore, J. Ellard