Arcturus

[ ahrk-too r-uh s, -tyoo r- ]
/ ɑrkˈtʊər əs, -ˈtyʊər- /

noun Astronomy.

a first-magnitude star in the constellation Boötes.

Origin of Arcturus

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

Related forms

Arc·tu·ri·an, adjective
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Examples from the Web for arcturus

British Dictionary definitions for arcturus

Arcturus

/ (ɑːkˈtjʊərəs) /

noun

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

Derived Forms

Arcturian, adjective

Word Origin for Arcturus

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

Science definitions for arcturus

Arcturus

[ ärk-turəs ]

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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