Just for finishers, time is up by clock (4)
I believe the answer is:
espy
'clock' is the definition.
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for espy that I've seen before include "See" , "Make out at a distance" , "Perceive" , "Spot; observe" , "Observe, notice" .)