Arcturus

[ahrk-too r-uh s, -tyoo r-] /ɑrkˈtʊər əs, -ˈtyʊər-/
noun, Astronomy
1.
a first-magnitude star in the constellation Boötes.
Origin
1352-75; < Latin < Greek Arktoûros, equivalent to árkt(os) bear + -oûros keeper; replacing Middle English arture < Middle French
Related forms
Arcturian, adjective
Examples from the web for Arcturus
  • It contains the third brightest star in the night sky, Arcturus.
British Dictionary definitions for Arcturus

Arcturus

/ɑːkˈtjʊərəs/
noun
1.
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
C14: from Latin, from Greek Arktouros, from arktos bear + ouros guard, keeper
Word Origin and History for 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."

Arcturus in Science
Arcturus
  (ärk-tr'əs)   
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.
Arcturus in the Bible

bear-keeper, the name given by the ancients to the brightest star in the constellation Bootes. In the Authorized Version (Job 9:9; 38:32) it is the rendering of the Hebrew word _'ash_, which probably designates the constellation the Great Bear. This word ('ash) is supposed to be derived from an Arabic word meaning night-watcher, because the Great Bear always revolves about the pole, and to our nothern hemisphere never sets.

Encyclopedia Article for Arcturus

one of the five brightest stars in the night sky, and the brightest star in the northern constellation Bootes, with an apparent visual magnitude of 0.05. It is an orange-coloured giant star about 37 light-years from the Earth. It lies in an almost direct line with the tail of Ursa Major (the Great Bear); hence its name, derived from the Greek words for "bear guard."

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