Fancy putting limit on grain (7)
I believe the answer is:
caprice
'fancy' is the definition.
(thesaurus)
'limit on grain' is the wordplay.
'limit' becomes 'cap' (capping is a kind of limiting).
'on' is a charade indicator (letters next to each other).
'grain' becomes 'rice' (rice is a kind of grain).
'cap'+'rice'='CAPRICE'
'putting' acts as a link.
(Other definitions for caprice that I've seen before include "Sudden whim" , "A whim or piece of fancy" , "Sudden change of mind" , "Whimsy" , "A whim, or piece of music in lively fanciful style" .)