τρισμύριοι

αι, α, Subst.
A. thrice ten thousand, 30,000, Hdt. 2.163, 7.184, Ar. Av. 1179, X. An. 7.8.[26], etc. :—in sg. with a collective Subst., ἵππος τρισμυρία thirty thousand horse, A. Pers. 315.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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