ejército

exerceo (Latin)

I harass, worry. I keep busy, keep at work, drive on; occupy, employ, exercise (something in a form of action). I oversee, superintend, operate. I work (at).

exercitus (Latin)

(poetic) a multitude, host, swarm, flock. A troop, body of attendants. An exercised, disciplined body of men, an army. The assembly of the people in the Centuria Comitiata, as being a military organization. Trouble, affliction.

ejército (Spanish)

Army.