Alcor

noun

Al·​cor (ˈ)al-¦kȯr 

astronomy

: a faint star of the fourth magnitude that is located near Mizar in the handle of the Big Dipper

And it's at the bend of the Dipper's handle that an interesting object resides. Look here to spot a "double" star. These two are known by their proper names, Mizar, and its fainter companion, Alcor, also called the "horse and rider."

—Dennis Mammana, Newsday, 28 May 2011

called also 80 Ursae Majoris

Word History

Etymology

borrowed from New Latin, perhaps borrowed from Arabic al-khawr "depression, gulf," a variant reading of the consonants in al-jawn literally, "black, black horse," a name for ε Ursae Minoris

First Known Use

1675, in the meaning defined above

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