The invention pertains to a spoiler (5) for an aerodynamically active surface of an aircraft (1), particularly for an airfoil of an aircraft, wherein said spoiler is supported on the aerodynamically active surface such that it is articulated about an axis (11) extending transverse to the air flow direction and can be adjusted relative to the air flow. According to the invention, the spoiler features two or more segments (6, 7) that are arranged behind one another referred to the air flow direction and extend transverse to the air flow direction, wherein said segments are connected to one another in an articulated fashion and can be adjusted to different angles referred to the air flow. The successively arranged segments of the spoiler (5) can be actuated, in particular, by means of an actuating device (8, 9, 10) in such a way that the rear segment (7) is adjusted relative to the air flow by a greater angle than the front segment (6).