Bolo (n.)youdaoicibaDictYouDict[Bolo 词源字典]
"traitor," 1917, from Paul Bolo, French adventurer shot for treason April 17, 1918; used in World War I with reference to pacifist propagandists; later somewhat assimilated to Bolshevik (q.v.).[Bolo etymology, Bolo origin, 英语词源]