Definitions:

1. A military or paramilitary personnel trained and responsible for operating a machine gun, and that play a crucial role in providing sustained, suppressive fire to support their unit in combat situations. NOUN
   • The machine gunner set up his position and began providing suppressive fire to cover the squad's advance.
2. A serviceman in the artillery. NOUN
   • A trained machine gunner knows how to effectively use cover while laying down suppressive fire.
3. An individual, typically a member of military or law enforcement, who is specifically trained to operate, maintain, and utilize machine guns. NOUN
   • With precision, the machine gunner aimed and unleashed a torrent of bullets.

Synonyms:

• artilleryman
• cannoneer
• gunner
• marksman