δίοπτρον

τό
A. means for seeing through, οἶνος γὰρ ἀνθρώπω δ. Alc. 53.
II. = διόπτρα 1, Hsch. s.v. ἀστραβιστήρ.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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