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

Arcturus first appeared in India, but as it makes its way through North America, it seems to be presenting feverish symptoms more commonly as well as mimicking allergies, specifically conjunctivitis.

From Salon • May 16, 2023

Arcturus isn’t the first variant that has shown an affinity for receptors in the eyes.

From Scientific American • May 12, 2023

For instance, a new omicron subvariant, XBB.1.16, nicknamed Arcturus, is becoming more prevalent throughout the United States.

From Washington Post • May 2, 2023

The three, Denebola, Spica, and Arcturus, mark the corners of a great equilateral triangle.

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