惩一警百 (懲一警百) chéng yī jǐng bǎi

chéng yī jǐng bǎi set phrase punish one, warn one hundred; to make an example of
Domain: Idiom 成语
Notes: Also written 惩一儆百 (CC-CEDICT '懲一警百'; Guoyu '懲一警百'; Mathews 1931 '懲一警百', p. 50)