Small drink brought up: time for larger one? (4)
I believe the answer is:
pint
'larger one?' is the definition.
The definition and answer can be both quantities as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'small drink brought up time' is the wordplay.
'small drink' becomes 'nip' (I've seen this before).
'brought up' is a reversal indicator (in a down clue, letters go up).
'time' becomes 't' (abbreviation).
'nip' reversed gives 'pin'.
'pin'+'t'='PINT'
'for' acts as a link.
(Other definitions for pint that I've seen before include "Standard measure of Guinness" , "Measure of the plain man's alcoholic drink" , "small amount" , "Liquid meassure - four gills" , "Half a quart" .)