Indian contribution to growth industry (5)
I believe the answer is:
hindu
'indian' is the definition.
(I've seen this before)
'contribution to growth industry' is the wordplay.
'contribution to' indicates a hidden word.
'HINDU' can be found hidden inside 'growth industry'.
(Other definitions for hindu that I've seen before include "Religious believer" , "Follower of great Indian religion" , "Follower of a major religion of the Indian subcontinent" , "Member of major Indian religion" , "Most of the Indians are" .)