'Army' in the Bible

"Listen! There's a noise on the mountains like that of a great multitude! Listen! There's an uproar among the kingdoms, like that of nations massing together! The LORD of the Heavenly Armies is mustering an army for battle.

Then the king of Assyria sent his field commander, along with a very large army, from Lachish to King Hezekiah at Jerusalem. When the field commander stopped at the aqueduct at the Upper Pool on the road to Laundryman's Field,

After this, the angel of the LORD went out and put to death 185,000 men in the Assyrian camp. When Hezekiah's army awakened in the morning there were all the dead bodies!