Abbreviation of 機関銃. Used in military, news, and technical contexts. Not the everyday word for machine gun; 機関銃 is more common in general use.
See also: 機関銃
The fighter plane is equipped with machine guns.
They shot down the enemy plane with the ship's machine-gun fire.
machine-gun strafing; machine-gun fire
Abbreviation of 機関銃 (きかんじゅう), combining the first character of 機関 (mechanism) and 銃 (gun).