Conclude model on French Island is nonproductive? (9)
I believe the answer is:
infertile
'nonproductive?' is the definition.
(thesaurus)
'conclude model on french island' is the wordplay.
'conclude' becomes 'infer' (inferring is a kind of concluding).
'model' becomes 't' (Ford Model T car).
'on' means one lot of letters go next to another.
'french island' becomes 'ile' ('island' in French).
'infer'+'t'+'ile'='INFERTILE'
'is' is the link.
(Other definitions for infertile that I've seen before include "So can't father" , "Barren" , "Fruitless" , "Not productive" .)