An Etymological Dictionary of the German Language/redlich

by Friedrich Kluge

redlich, adj., ‘honest, candid,’ from MidHG. rędelîch, ‘eloquent, intelligent, upright, sturdy,’ OHG. rędilîh, ‘intelligent’; allied to OHG. rędia, MidHG. ręde, ‘understanding, account.’ See Rede.