One feels worker wants girl back (7)
I believe the answer is:
antenna
'one feels' is the definition.
(an antenna feels things)
'worker wants girl back' is the wordplay.
'worker' becomes 'ant' (worker is a type of ant).
'wants' means one lot of letters go next to another.
'girl' becomes 'anne' (girl's name).
'back' is a reversal indicator.
'anne' reversed gives 'enna'.
'ant'+'enna'='ANTENNA'
(Other definitions for antenna that I've seen before include "Insect's sensory appendage" , "Feature of dish" , "Aerial - insect feeler" , "Insect's feeler" , "Radio aerial" .)