Advance guard

a body of troops going before the main force to clear the way, guard against surprise, etc.
historical examples

but meanwhile, on the 14th september, the advance guard of the french army entered the city.
moscow fred whishaw

we’ve just received the first communique from the advance guard, sir.
martian v.f.w. g.l. vandenburg

almost at the same moment, the soldiers of the advance guard arrived.
herodias gustave flaubert

the advance guard had suffered, but their fire had quelled that of the enemy.
through three campaigns g. a. henty

but still there was a chance that they might be the advance guard of a big body of troops.
the ocean wireless boys on the pacific wilbur lawton

the pioneer and airship divisions are placed with the advance guard.
operations upon the sea franz edelsheim

the marquis lafayette at this time commanded the advance guard of washington’s army, composed of six battalions of light infantry.
the student’s life of washington; condensed from the larger work of washington irving washington irving

“they form the advance guard of our foes,” said the burgomaster.
the lily of leyden w.h.g. kingston

nag-una ang mga adbans gard kay silay magpriparar, the advance guard has gone ahead because they will get things ready.
a dictionary of cebuano visayan john u. wolff

there goes an advance guard of the foot, marching to the front of the horse.
marcus: the young centurion george manville fenn

noun
a military unit sent ahead of a main body to find gaps in enemy defences, clear away minor opposition, and prevent unexpected contact
a temporary military detachment sent ahead of a force to prepare for a landing or other operation, esp by making reconnaissance