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Eridanus

[ih-rid-n-uh s]
noun, genitive E·rid·a·ni [ih-rid-n-ahy] /ɪˈrɪd nˌaɪ/. Astronomy.
  1. the River, a large southern constellation between Cetus and Orion, containing the bright star Achernar.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for eridanus

Eridanus

noun Latin genitive Eridani (ɛˈrɪdəˌnaɪ)
  1. a long twisting constellation in the S hemisphere extending from Orion to Hydrus and containing the first magnitude star Achernar

Word Origin for Eridanus

from Greek Eridanos river in Italy (sometimes identified with the Po) into which, according to legend, Phaëthon fell
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