(Εὐρυβάρης), an Argive, the commander of 1000 volunteers who went to the assistance of the Aeginetans in their war with the Athenians just before the Persian invasion. He had practised the pentathlum, and challenged four of the Athenians to single combat. Three he slew, but fell himself by the hand of the fourth. (Hdt. 6.92, 9.75.)