(~s)
If you describe something or someone as an ~, you mean they are mysterious or difficult to understand.
Iran remains an ~ for the outside world.
= mystery
N-COUNT: usu sing
(~s)
If you describe something or someone as an ~, you mean they are mysterious or difficult to understand.
Iran remains an ~ for the outside world.
= mystery
N-COUNT: usu sing
Collins COBUILD. Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) . 2012