ὀπτήρ
From LSJ
Νόμων ἔχεσθαι (Νόμοις ἕπεσθαι) πάντα δεῖ τὸν σώφρονα → Legibus haerere sapiens debet firmiter → Dem Klugen ist Gesetzestreue stete Pflicht
English (LSJ)
ῆρος, ὁ, (ὄψ)
A one who looks or spies, spy, scout, Od. 14.261, A.Supp.185, S.Aj.29. II one who has seen, Id.Ichn.77 ; eye-witness, Antipho 5.27, X.Cyr.4.5.17.