to suddenly become covered in sth :
Her face broke out in a rash.
He broke out in a cold sweat (= for example, through fear) .
to suddenly become covered in sth :
Her face broke out in a rash.
He broke out in a cold sweat (= for example, through fear) .
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005