ἰδρεία

ἴδρις

A. knowledge, skill, ἰδρείῃ πολέμοιο Il. 16.359; οὐδέ τι ἰδρείῃ (Aristarch. for vulg. οὐδέ τ’ ἀϊδρείῃ) 7.198, cf.A.R. 2.72, Q.S. 4.226, Theoc. 22.85.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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