Arcturus

[ ahrk-toor-uhs, -tyoor- ]

/ ɑrkˈtʊər əs, -ˈtyʊər- /

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noun Astronomy.

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

OTHER WORDS FROM Arcturus

Arc·tu·ri·an, adjective

Words nearby Arcturus

arctiid, Arctogaea, Arctogaean, Arctogea, arctophile, Arcturus, arcuate, arcuate artery, arcuate artery of kidney, arcuate fiber, arcuate ligament

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use Arcturus in a sentence

The comet will be near Arcturus, which sits low on the horizon.
Here’s how to see Leonard’s Comet, the brightest comet all year|Margo Milanowski|December 4, 2021|Popular-Science
Designs had to be optimized for Methanians, buildable using Earth materials and methods, and realistically functional within Arcturus’s parameters.
Extraterrestrial engineering|Katie McLean|February 24, 2021|MIT Technology Review
Arnold unveiled the Arcturus project in 1951, and the assignment soon expanded from home products to transportation and farming technologies.
Extraterrestrial engineering|Katie McLean|February 24, 2021|MIT Technology Review
Even though the Arcturus project was only one piece of Arnold’s engineering course—other assignments focused on reimagining what he called “more prosaic, earthly designs” like railroad boxcars—industry and the media took notice.
Extraterrestrial engineering|Katie McLean|February 24, 2021|MIT Technology Review

Farmyards might host a horse named Arcturus or a chicken called Cleopatra.
Noble virtues, bad history: How Greece and Rome influenced America’s founders|Charles King|November 6, 2020|Washington Post
But a moment later he referred to the stupendous fact of Arcturus being fifty thousand times as big as the sun.
Mark Twain, A Biography, 1835-1910, Complete|Albert Bigelow Paine
If the axis of the earth pointed toward Arcturus instead of Polaris, would the seasons be any different from what they are now?
A Text-Book of Astronomy|George C. Comstock
Arcturus has been moving ever since the time of Job at the rate of probably more than 200 miles per second—possibly 300 miles.
The Popular Science Monthly, September, 1900|Various
Papilio Arcturus and some allied species, are of a golden-green, changing to blue, or to glowing purple.
The Romance of Natural History, Second Series|Philip Henry Gosse
Years ago, Arcturus and myself met a gentleman from China who knew the language.
An English Grammar|W. M. Baskervill and J. W. Sewell

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 of Arcturus

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

Scientific definitions for Arcturus

Arcturus

[ ärk-tur′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.