Fighting using groups of irregular troops within areas occupied by the enemy(noun)
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Use "guerrilla warfare" in a sentence
"Cornwallis offered clemency to all those willing to swear allegiance to the king, and many hastened to do so; others, though not the majority, retreated to the swamps and mountains of the interior and under Francis Marion (the “Swamp Fox”), Thomas Sumter (the “Carolina Gamecock”), Andrew Pickens, and other partisan leaders carried on guerrilla warfare against the occupation force."
"On guerrilla warfare and counterinsurgency, see Robert B. Asprey, War in the Shadows: The Guerrilla in History, vol."
"Their greatest leader, Viriathus, had bedeviled the Romans with eight years of guerrilla warfare 148139 B.C."