Polyphemus was famous as the Cyclops who was made drunk, and then blinded, by Odysseus (who had disguised himself as a stranger called Nobody). He was a son of Poseidon by the sea nymph Thoösa, and he lived with other Cyclopes on the island of Sicily.
He must have made quite a name for himself there, for Polyphemus means 'many tales' (i.e. notorious) or else 'many loud cries' (i.e. brash and boastful), from polys, 'many' and pheme, 'words', 'rumour', 'reputation'. This was perhaps a propitious name for the Argonaut Polyphemus who was the son of Eilatus and Hippea.