In Greek mythology, Aegyptus, or properly Aígyptos in Greek ("supine goat"), was the king of Egypt (which took its name from his, according to folk etymology; see the article Copt), the son of Belus and father of fifty sons who were all but one murdered by the fifty daughters of Aegyptus' twin brother, Danaus.
Aegyptus commanded that his sons marry the Danaides and Danaus fled to Argos, ruled by King Pelasgus.
Aegyptus is also the Latin spelling of Egypt, and the correct denomination for the Roman province.