A fighter aircraft is a military aircraft designed primarily for air-to-air combat against other aircraft, as opposed to bombers and attack aircraft, whose main mission is to attack ground targets. The hallmarks of a fighter are its speed, maneuverability, and small size relative to other combat aircraft.
Many fighters have secondary ground-attack capabilities, and some are designed as dual-purpose fighter-bombers; often aircraft that do not fulfill the standard definition are called fighters. This may be for political or national security reasons, for advertising purposes, or other reasons.
A fighter's main purpose is to establish air superiority over a battlefield. Since World War I, achieving and maintaining air superiority has been considered essential for victory in conventional warfare.
The word "fighter" did not become the official English-language term for such aircraft until after World War I. In the British Royal Flying Corps and Royal Air Force these aircraft were referred to as "scouts" into the early 1920s. The U.S. Army called their fighters "pursuit" aircraft from 1916 until the late 1940s. In most languages a fighter aircraft is known as a hunter, or hunting aircraft (avion de chasse, jagdflugzeuge, avión de caza etc.). Exceptions include Russian, where a fighter is an "иÑтребитель" (pronounced "istrebitel"), meaning "exterminator", and Hebrew where it is "matose krav" (literally "battle plane").