A heavy fighter is a historic category of fighter aircraft produced in the 1930s and 1940s, designed to carry heavier weapons or operate at longer ranges than light fighter aircraft. To achieve performance, most heavy fighters were twin-engine, and many had multi-place crews; this was in contrast to light fighters, which were typically single-engine and single-crew aircraft. In Germany, these larger fighters were known as Zerstörer ("destroyer").

Fighter aircraft are military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air superiority of the battlespace. Domination of the airspace above a battlefield permits bombers and attack aircraft to engage in tactical and strategic bombing of enemy targets.