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
Denver Post, 15 Feb. 1996called 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