IN ... FLAT


Meaning of IN ... FLAT in English

( informal ) used with an expression of time to say that sth happened or was done very quickly, in no more than the time stated :

They changed the wheel in three minutes flat (= in exactly three minutes) .

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