Time to request some work (4)
I believe the answer is:
task
'some work' is the definition.
(task is a kind of work)
'time to request' is the wordplay.
'time' becomes 't' (abbreviation).
'to request' becomes 'ask' (to ask is to request something).
't'+'ask'='TASK'
(Other definitions for task that I've seen before include "Give mission" , "Errand, duty" , "exercise" , "Piece of work to be done" , "Arduous bit of work" .)