Moment, second (7)
I believe the answer is:
instant
I believe this clue is a double definition.
'moment' is the first definition.
(I know that instant is a type of moment)
'second' is the second definition.
(I know that instant is a type of second)
(Other definitions for instant that I've seen before include "Short time; immediate" , "Tick" , "This coffee is made from powder" , "This coffee comes in powder form" , "Short time, of the current month" .)