(Μεγακλῆς).
1. A Syracusan, brother of Dion the son of Hipparinus, and brotherin-law of the elder Dionysius, to whose government he lent his support, and on one occasion when the tyrant was inclined to despair, urged him not to abandon the sovereignty until absolutely compelled to do so (Diod. 20.78; but see Wesseling's note). He, however, in common with his brother, became discontented at the government of the younger Dionysius, and accompanied Dion in his flight from Syracuse, B. C. 358 (Diod. 16.6). He afterwards also took part with him in his expedition to Sicily, and when Dion made himself master of Syracuse, Megacles accompanied him on his triumphal entry into the city, and was associated with him in the chief command (Plut. Dio 28, 29). But from this period his name is not again mentioned.