'Army' in the Bible

And three of the thirty chiefs went down to the rock to David, to the cave of Adullam, when the army of the Philistines was encamped in the valley of Rephaim.

And it shall be, when thou hearest the sound of marching in the tops of the mulberry-trees, that then thou shalt go out to battle; for God will have gone forth before thee to smite the army of the Philistines.

And David did as God commanded him; and they smote the army of the Philistines from Gibeon even to Gezer.

And it came to pass at the time of the return of the year, at the time when kings go forth, that Joab led forth the power of the army, and laid waste the land of the children of Ammon, and came and besieged Rabbah. But David abode at Jerusalem. And Joab smote Rabbah, and overthrew it.

and after Ahithophel was Jehoiada the son of Benaiah, and Abiathar; and Joab was captain of the king's army.