black ops
noun [ plural or U ] uk/blæk ˈɒps/ us/blæk ˈɑːps/
（由政府或机构下令进行却对外否认的、尤指非法的）秘密军事行动
secret military activities, especially illegal ones, that are ordered by a government or organization but that they will not admit to having ordered
a black ops agent/team 秘密行动特工/团队