Round of applause for worker (4)
I believe the answer is:
hand
This clue is a double definition.
'round of applause' is the first definition.
(as in a 'big hand', a round of applause)
'worker' is the second definition.
(hand is a kind of worker)
'for' is the link.
(Other definitions for hand that I've seen before include "writing" , "Unclenched fist" , "Hired worker" , "Clock-pointer" , "Help < and applause" .)