A.to be relied on, sure, certain, οὔ οἱ ἔπειτα ἄρκιον ἐσσεῖται φυγέειν he shall have no hope to escape, Il.2.393; νῦν ἄρκιον ἢ ἀπολέσθαι ἠὲ σαωθῆναι one of these is certain, to perish or be saved, 15.502; μισθὸς δέ οἱ ἄ. ἔσται a sure reward, 10.304, cf. Od.18.358, but, a sufficient reward in Hes.Op.370; βίος ἄ. ib.501,577.
II. enough, sufficient, ἄρκιον εὑρεῖν to be sure of having enough, ib.351, A.R.2.799, Theoc. 8.13; ὄφρα . . σφίσιν ἄρκιος εἴη that he might be sufficient for them, Id.25.190; “δέμας ἄρκιος” Opp.C.3.185, cf. H.3.601; helpful, useful, “παντὶ γὰρ ἄ. ἐστι” Nic.Th.508, cf. Opp.C.3.173; ἄρκια νούσων remedies against . . , Nic.Th.837: c. inf., able to . . , Call.Fr.51a, cf. Cer.35. Adv. “-ίως” Hsch.