γνώστης

ου, ὁ
A. one that knows, τῶν ἐθῶν Act.Ap. 26.3; τοῦ εὐαγγελίου Sammelb. 421.1 (iii A. D.): esp.one who knows the future, diviner, LXX 1 Ki. 28.3.
II. = γνωστήρ, surety, γ. τῆς πίστεως Plu. Flam. 4; expert witness or valuer, PLips. 106.10 (i A. D.).
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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