belonging to a group or an organization and therefore able to get information that is not available to other people :
The thieves must have had someone on the inside helping them.
belonging to a group or an organization and therefore able to get information that is not available to other people :
The thieves must have had someone on the inside helping them.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005