People working - they’re on the clock (5)
I believe the answer is:
hands
'they're on the clock' is the definition.
(I've seen this in another clue)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for hands that I've seen before include "Measurements for horses" , "Players' cards" , "skill in handling reins" , "Passes" , "Workmen" .)