noun

a group of troops stationed in a fortress or town to defend it.

the entire garrison was mustered on the parade ground

armed force,force,military detachment,military unit,unit,platoon,brigade,regiment,squadron,battalion,company,legion,corps,troops,militia,soldiers

verb

provide (a place) with a group of troops.

air reconnaissance showed the Germans had not garrisoned the island

defend,guard,protect,preserve,fortify,barricade,shield,secure,man,occupy,supply with troops