An airfoil in a gas turbine engine includes an outer wall, a cooling fluid cavity, and a cooling system. The outer wall has a leading edge, a trailing edge, a pressure side, a suction side, and radially inner and outer ends. The cooling fluid cavity is defined in the outer wall, extends generally radially between the inner and outer ends of the outer wall, and receives cooling fluid for cooling the outer wall. The cooling system receives cooling fluid from the cooling fluid cavity for cooling the trailing edge portion of the outer wall and includes a cooling fluid chamber defined by opposing first and second sidewalls that include respective alternating angled sections that provide the cooling fluid chamber with a zigzag shape.