“Front cul-de-sac setback line” means a line which forms a vertical plane concentrically parallel to the right-of-way line of the street on the cul-de-sac (bulb) and a line parallel to the minimum required setback from the right-of-way line of the remainder of the cul-de-sac (road leading to the bulb). (Ord. 1985-6 § 4 (part); prior code § 5-2-2(FFF))