A fighter pilot was a military aviator explicitly trained to engage other aircraft. On the planet Earth, fighter pilots were used by the governments and militaries of many countries during the 20th century.
The Battle of Britain, an aerial conflict between Germany and Great Britain during Earth's Second World War, utilized fighter pilots on both sides of the battle. The Battle of Britain was one of Julian Bashir and Miles O'Brien's favorite holoprograms at Quark's holosuites, taking the role of two RAF pilots in a squadron that included Clive. (DS9: "Homefront")
In 2373, Elim Garak lightly chided O'Brien for "spend[ing] hours in the holosuites dressed up as [a] fighter pilot, reliving ancient battles", implying that despite his current occupation as an engineer, he was still a soldier at heart. (DS9: "Empok Nor")
In 2375, Doctor Bashir proposed a toast to Starfleet helmsman, Lieutenant Hector Ilario, after he successfully evaded six Jem'Hadar fighters while at the helm of the USS Defiant. He said he was "living proof that Starfleet Academy produced the finest fighter pilots in the galaxy". (DS9: "Field of Fire")