Rad'dai (Heb. Radday', רִדִּי, tramspling; Sept. ῾Ραδδαϊv v. r. Ζαβδαϊv), the fifth of the seven sons of Jesse, and an elder brother of king David (1Ch 2:14). B.C. 1068. He does not appear in the Bible elsewhere than in this list, unless he be, as Ewald conjectures (Geschichte, iii, 266, note), identical with Rei (q.v.).