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, the dominant Omicron subvariant dubbed Arcturus, has been manifesting as pinkeye.

From Los Angeles Times • Jul. 28, 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 strain, known officially as XBB.1.16 and colloquially as Arcturus, is a subvariant of Omicron.

From Scientific American • May 12, 2023

Yet Regulus, although ranked as a first-magnitude star, and of great repute among the ancient astrologers, is far inferior in brilliancy to such stars as Capella and Arcturus, to say nothing of Sirius.

From Astronomy with an Opera-glass A Popular Introduction to the Study of the Starry Heavens with the Simplest of Optical Instruments by Serviss, Garrett Putman