large but transportable armament
"The regiment deployed its heavy artillery to support the advancing infantry without needing a railway line."
an army unit that uses big guns
"The artillery fired their big guns at the enemy positions from a safe distance behind the hills."
Large projectile weapons, transportable and usually operated by more than one person; usually various types of cannon, but rocket artillery also exists.
"The heavy artillery pieces were assembled on the ridge to bombard enemy positions from a safe distance."
In plain English: Artillery is heavy guns used by armies to shoot far and hard at enemies from a distance.
"The army moved their artillery to the front lines before dawn."
Usage: The term refers specifically to the heavy weaponry itself rather than the soldiers who operate them. Avoid using "artillery" as a verb or attributing human qualities to it in casual speech.
From Middle English artillerie, from Old French artillerie ("collection of military engines, crossbows, lances etc."), from artillier ("to equip, provide with contraptions"), alteration of atiller ("to arrange, adjust, put on clothes or, especially, pieces of armour") (influenced by art), itself from Vulgar Latin apticlō < apticulō, from Latin aptō ("to make capable").