游击战

Mao Zedong's 16-character maxim defined Chinese Communist guerrilla doctrine: 敌进我退，敌驻我扰，敌疲我打，敌退我追 ('enemy advances, we retreat; enemy halts, we harass; enemy tires, we strike; enemy retreats, we pursue'). 游 (roving) plus 击 (strike) plus 战 (warfare) = the classic translation of 'guerrilla' coined for this military style.

Frequently used figuratively: 打 游击战 can describe any irregular, hit-and-run approach - e.g. street vendors evading inspectors, or salespeople working without a fixed office.