(adj.) conducted with or marked by hidden aims or methods; 'clandestine intelligence operations'; 'cloak-and-dagger activities behind enemy lines'; 'hole-and-corner intrigue'; 'secret missions'; 'a secret agent'; 'secret sales of arms'; 'surreptitious mobilization of troops'; 'an undercover investigation'; 'underground resistance' .
整理:凯瑟琳
杰弗里整理