What is "cynaegirus"

Cynegeirus, also spelled Cynaegeirus or Cynegirus ( Kynegeiros or Kynaigeiros; died 490 BC) was an ancient Greek hero of Athens and had three siblings. His two brothers were the playwright Aeschylus and Ameinias, hero of the battle of Salamis, while his sister was Philopatho , the mother of the Athenian tragic poet Philokles. He was the son of Euphorion from Eleusis and member of the Eupatridae, the ancient nobility of Attica.