(SMALL AMOUNT) [noun] [U] - used in expressions describing how small an amount or period of time isIn a matter of seconds, the building was in flames.The interview was over in a matter of minutes.She complained he had short-changed her, but it was only a matter of a few pence.
MATTER
Meaning of MATTER in English
Cambridge English vocab. Кембриджский английский словарь. 2012