Contemporary with office worker (4)
I believe the answer is:
temp
'office worker' is the definition.
(I've seen this before)
'contemporary with' is the wordplay.
'with' says the answer is hidden in the clue.
'TEMP' is hidden within 'contemporary'.
(Other definitions for temp that I've seen before include "Transitory office worker" , "Transient office worker" , "Non-permanent worker" , "Short-term worker, in short" , "relief" .)