[1] This primary gloss -- before the rest of the entry turns to matters of law, history and historiography -- indicates that the (feminine) headword comes from a philosophical context; see generally LSJ s.v. ku/rios, II.1.
[2] Entry thus far = Photius, Lexicon kappa1247 Theodoridis, and likewise or similarly elsewhere (e.g. Pollux, Onomasticon 1.67.3). Perhaps a gloss on Demosthenes 21.84 (and 21.93), 'the statutory [day]' when a lawsuit in classical Athens had to come to court. And perhaps more broadly related to the Athenian 'sovereign' assembly-meeting, one per prytany (thus ten per year) in Aristotle's time; see ?Aristotle, Athenaion Politeia 43.4-6 (web address 1), and cf. epsilon 470, kappa 2760.
[3] Quotation (and incident -- not likely to be Athenian) unidentifiable.
[4] cf. epsilon 2766 (end).
[5] A variation on Polybius fr. 45 Büttner-Wobst; cf. epsilon 3102.