גִּיסָא I, Y. Snh. III, 21ᵇ bot. אֲגִיסֵיה דר׳ וכ׳ R. H.’s brother-in-law.—Pl. גִּיסֵי. Snh. 28ᵇ אחי וג׳ brothers and brothers-in-law (two brothers having married two sisters). Ib. תרי ג׳.