(anc. geog.) a river of Attica, falling into the Ilissus.—Another Eridanus, the more ancient name of the Padus, an appellation ascribed by Pliny to the Greeks; followed in this by Virgil. It rises in mount Vesulus, in the Alpes Cottiae, and dividing the Cispalpine Gaul into the Cispadana and Transpadana, and swelled on each hand with no inconsiderable rivers from the other Alps and the Apennine, falls at seven mouths into the Adriatic. Famous in mythology, from the story of Phaeton; whose filters, the Helias, were here changed into poplars, according to Ovid.

astronomy, a constellation of the southern hemisphere, in form of a river.—The stars in the constellation Eridanus, in Ptolemy's catalogue, are 34; in Tycho's, 19; and in the British Catalogue, 84.