Meaning of main guard | Babel Free

Definitions

1. A body of troops comprising the chief guard units, especially a unit of cavalry on the wing of a camp towards the enemy, or a group of soldiers in a fortress responsible for dealing with disturbers of the peace.
2. The keep of a castle; a guardhouse or building in a fortress where such a body of troops is lodged.

Examples

“[A]fter an obstinate engagement, in which divers wounds were given and received, every soul of them was taken, and conveyed to the main-guard, where the commanding officer […] set them all at liberty […].”

CEFR level