guerrilla
guer.ril.la or gue.ril.la \g*-'ril-*\ n [Sp guerrilla, fr. dim. of guerra war, of Gmc origin; akin to OHG (Xwerra strife - more at WAR archaic 1: irregular warfare by independent bands 2: one who engages in irregular warfare esp. as a member of an independent unit carrying out harassment and sabotage