If you say that someone or something is ~, you are emphasizing that they are very unpleasant or annoying. (FORMAL)
He was an ~ bore.
= unbearable
ADJ emphasis
insufferably
His letters are insufferably dull...
ADV: ADV adj
If you say that someone or something is ~, you are emphasizing that they are very unpleasant or annoying. (FORMAL)
He was an ~ bore.
= unbearable
ADJ emphasis
insufferably
His letters are insufferably dull...
ADV: ADV adj
Collins COBUILD. Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) . 2012