1. a large organized group of soldiers trained and equipped for war
2. a very large number of people or things

Examples

• The army marched across the battlefield.
• She joined the army after graduating from college.
• The country’s army was well-trained and disciplined.
• An army of volunteers helped clean up after the storm.
• The general commanded an army of 50,000 soldiers.
• An army of ants invaded the picnic area.
• The army defended the border against invasion.