διοπτήρ

ῆρος, ὁ
A. spy, scout, στρατοῦ Il. 10.562: in late Prose, Agath. 2.2.
II. διάγγελοι καὶ διοπτῆρες, the optiones and tesserarii of the Romans, Plu. Galb. 24.
III. = διόπτρα 111, Aët. 16.105.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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