Lewis & Short

Augīas or Augēas, ae (Augēus, Hyg. Fab. 30, and App. Orthog. Fragm. 33), m., = Αὐγείας, a son of the Sun and Naupidame, the daughter of Amphidamas, king of Elis, one of the Argonauts, Hyg. Fab. 14. His stable, containing three thousand head of cattle, uncleansed for thirty years, was cleaned in one day by Hercules, at the command of Eurystheus, Serv. ad Verg. A. 8, 300. Hence the prov.: Cloacas Augiae purgare, to cleanse an Augean stable, i. e. to perform a difficult and unpleasant labor, Sen. Apocol. (Gr., καθαίπειν την κόπρον τοῦ Αὐγειου).