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Arcturus

[ahrk-too r-uh s, -tyoo r-]
noun Astronomy.
  1. a first-magnitude star in the constellation Boötes.
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Origin of Arcturus

1352–75; < Latin < Greek Arktoûros, equivalent to árkt(os) bear + -oûros keeper; replacing Middle English arture < Middle French
Related formsArc·tu·ri·an, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for arcturus

Historical Examples

  • Arcturus is the fourth brightest star in the northern hemisphere.

    A Field Book of the Stars

    William Tyler Olcott

  • Been computing the orbit of the wreckage of the Arcturus around Jupiter.

    Spacehounds of IPC

    Edward Elmer Smith

  • It has been computed that Arcturus is in mass 500,000 times as large as our sun!

  • Arcturus was a roving beast of the plains; he went in droves in his day.

  • The Arcturus was detained several days discharging and taking in freight.

    The Land of Thor

    J. Ross Browne


British Dictionary definitions for arcturus

Arcturus

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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Derived FormsArcturian, adjective

Word Origin

C14: from Latin, from Greek Arktouros, from arktos bear + ouros guard, keeper
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for arcturus

Arcturus

late 14c., bright star in the constellation Bootes (also used of the whole constellation), from Latin Arcturus, from Greek Arktouros; anciently associated with the Bear, and its name is Greek for "guardian of the bear." See arctic; second element is from ouros "watcher, guardian, ward" (see warrant (n.)).

Arcturus in the Bible (Job ix:9 and xxxviii:32) is a mistranslation by Jerome (continued in KJV) of Hebrew 'Ayish, which actually refers to the "bowl" of the Big Dipper. In Israel and Arabia, the seven stars of the Great Bear seem to have been a bier (the "bowl") followed by three mourners. In the Septuagint it was translated as Pleiada, which is equally incorrect. The double nature of the great bear/wagon (see Big Dipper) has given two different names to the constellation that follows it: Arktouros "bear-ward" and bootes "the wagoner."

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Online Etymology Dictionary, © 2010 Douglas Harper

arcturus in Science

Arcturus

[ärk-turəs]
  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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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.