(Δέρδας), a Macedonian chieftain, who joined with Philip, brother of Perdiccas II., in rebellion against him. Athens entered into alliance with them, a step, it would seem, of doubtful policy, leading to the hostility of Perdiccas, and the revolt, under his advice, of Potidaea, and the foundation of Olynthus. The Athenian generals who arrived soon after those events acted for a while against Perdiccas with them. (Thuc. 1.57_59.) Derdas himself probably died about this time, as we hear of his brothers in his place (100.59), one of whom Pausanias probably was. (100.61.)