Jastrow: רוּבָּא

רוּבָּא ch. same. Ḥull. 11ᵃ מנא הא מילתא … בתר ר׳ whence do we derive the rule laid down by the Rabbis, that we are guided by the majority? Ib. ר׳ דאיתיה קמן a majority which is before us, a majority of a definite number; ר׳ דליתיה קמן כגון וכ׳ a majority of an indefinite number, as for instance, the case of a minor yabam (Yeb. XIII, 12, when we are guided by the principle that the majority of persons are not impotent). B. Kam. 46ᵇ ר׳ דאנשי לרדיא וכ׳ most people buy animals for ploughing. Ib.; B. Bath. 92ᵇ, v. אִיסּוּרָא; a. v. fr.—Pl. רוּבֵּי. Ḥull. 28ᵇ תרי ר׳ … ליכא Rashi (ed. רובא) two larger portions of one object cannot be assumed, i.e. if an object is divided into two equal parts, you cannot apply the principle that either half may be ritually considered as if it were the larger portion.