(~s)
A ~ is an electronic device which alters the sound of a radio or telephone message so that it can only be understood by someone who has special equipment.
N-COUNT
(~s)
A ~ is an electronic device which alters the sound of a radio or telephone message so that it can only be understood by someone who has special equipment.
N-COUNT
Collins COBUILD. Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) . 2012