16. εὐκαιρίαν. See Lob. Phryn. 126. εὐκαιρία is admitted as a classical word, but the verb εὐκαιρεῖν is rejected. προκόπτειν and προκοπὴ are an instance of the reverse. Cp. Cic. de Offic. I. 40, ‘Tempus actionis opportunum Græce εὐκαιρία, Latine appellatur occasio.’