σύγγαμβροι

οἱ
A. the husbands of two sisters, Poll. 3.32, etc.: sg., brother-in-law, PCair.Zen. 475.11 (iii B.C.), MAMA 3.493 (Corycus); = congener, Gloss.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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