Wanting to include hard worker (3)
I believe the answer is:
ant
'hard worker' is the definition.
'wanting to include' is the wordplay.
'to include' says the answer is hidden in the clue.
'ANT' can be found hidden inside 'wanting'.
(Other definitions for ant that I've seen before include "` `Go to the ... thou sluggard' '" , "colonist" , "Hill-dweller" , "One working hard" , "Colonial insect?" .)