Achernar

noun

Acher·​nar ˈā-kər-ˌnär 

astronomy

: a blue star with an apparent magnitude of about 0.50 that is the brightest star in the constellation Eridanus

Winding its way across the southern horizon is the lesser-known constellation Eridanus, also known as the "River Eridanus." Ptolemy assigned 38 stars to this constellation, of which Achernar, located at the end of the "river," is the ninth brightest star in the sky.

—Denver Post, 15 Feb. 1996

called also Alpha Eridani

Word History

Etymology

borrowed from New Latin Achernar, Acharnar, going back to Medieval Latin Acarnar, transcription of Arabic ākhir an-nahr "end of the river," rendering its Ptolemaic designation as the bright star at the end of the river (Eridanus)

First Known Use

1679, in the meaning defined above

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