tenaz
From LSJ
Ὥσπερ οἱ ἐρωτικοὶ ἀπὸ τῶν ἐν αἰσθήσει καλῶν ὁδῷ προϊόντες ἐπ' αὐτὴν καταντῶσι τὴν μίαν τῶν καλῶν πάντων καὶ νοητῶν ἀρχήν → Just as lovers systematically leave behind what is fair to sensation and attain the one true source of all that is fair and intelligible
Spanish > Greek
δυσέκλυτος, δύστρεπτος, ἀτειρής, ἐνδελεχής, ἀδιάτροπος, ἀμάλθακτος, ἀτενής, ἀμαιμάκετος