insider
noun [ C ] uk/ɪnˈsaɪ.dər/ us/ɪnˈsaɪ.dɚ/
内部的人，知情人，了解内幕者
someone who is an accepted member of a group and who therefore has special or secret knowledge or influence
According to insiders, the committee is having difficulty making up its mind. 据知情人称，委员会很难作出决定。