1.An irregular mode of carrying on war, by the constant attacks of independent bands, adopted in the north of Spain during the Peninsular war.
2.One who carries on, or assists in carrying on, irregular warfare; especially, a member of an independent band engaged in predatory excursions in war time. Note: The term guerrilla is the diminutive of the Spanish word guerra, war, and means petty war, that is, war carried on by detached parties; generally in the mountains.... A guerrilla party means, an irregular band of armed men, carrying on an irregular war, not being able, according to their character as a guerrilla party, to carry on what the law terms a regular war.
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