ἀναπότρεπτος
From LSJ
εἰργάζοντο λογάδην φέροντες λίθους καὶ ξυνετίθεσαν ὡς ἕκαστόν τι ξυμβαίνοι → they went to work bringing the stones as they picked them out and put them together as each one happened to fit
Spanish (DGE)
-ον
firme, irrevocable γνώμη PMasp.98.4 (VI d.C.)
•como glos. a ἀλίαστος Sch.Er.Il.2.797 (p.170).