οὐρεύς

ῆος, ὁ
A. = οὖρος, φύλαξ, a guard, warder, cf. Arist. Po. 1461a10; but it may well mean mules here, as in other places, and the Sch. give both explanations.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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