The sovereign assembly of Athenian citizens, which voted on laws, war and policy and elected certain officials.
In more detail
In Aristotle's account the presiding committee (prytaneis) convened the Ekklesia four times in each prytany, one meeting being the 'sovereign' assembly that ratified the continuation of magistrates; attendance was paid. The Council of 500 prepared the agenda; the Assembly's decisions were not confined to the city's laws but also covered war and foreign policy.