1. A military commander or officer in charge of a thousand soldiers or a division of a thousand men.
Usage: archaic; historical; from Greek chiliarchos

Examples

• The chiliarch led his thousand troops across the valley.
• In ancient Greek armies, a chiliarch held significant authority over a large contingent of soldiers.
• The general appointed a trusted chiliarch to oversee the left flank of the army.
• Historical texts describe the chiliarch as a rank between the captain and the general.