Amount of time, very little (6)
I believe the answer is:
minute
This clue is a double definition.
'amount of time' is the first definition.
(unit of time)
'very little' is the second definition.
(I've seen this before)
(Other definitions for minute that I've seen before include "Small amount of time" , "Sixty seconds" , "Brief note" , "Infinitesimal" , "Barely perceptible" .)