ἀκουστός

ή, όν
A. heard, audible, h.Merc. 512, Hp. Insomn. 86, Pl. Ti. 33c, Phld. Herc. 698.20, etc.; opp. θεατός, Isoc. 2.49.
II. that should be heard, with neg., δεινόν, οὐκ ἀ. S. OT 1312, cf. E. Andr. 1084.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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