διοπτρικός

ή, όν, ἡ
A. of, belonging to the use of the διόπτρα 1, ὄργανον δ., = διόπτρα, Str. 2.1.35; τὰ δ. the science of dioptrics, Plu. 2.1093e: also ‐κή,ἡ, Procl in Euc. p.42 F.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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