SWEAR TO STH


Meaning of SWEAR TO STH in English

( informal ) to say that sth is definitely true :

I think I put the keys back in the drawer, but I couldn't swear to it (= I'm not completely sure) .

Oxford Advanced Learner's English Dictionary.      Оксфордский английский словарь для изучающик язык на продвинутом уровне.