Competitor for place on river an enterprising sort (13)
I believe the answer is:
industrialist
'an enterprising sort' is the definition.
The answer and definition can be both people as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
'competitor for place on river' is the wordplay.
'competitor' becomes 'trialist' (someone competing in a sports trial).
'for' means one lot of letters go next to another (I've seen this in other clues).
'place on river' becomes 'indus' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'trialist' put after 'indus' is 'INDUSTRIALIST'.
Can you help me to learn more?
(Other definitions for industrialist that I've seen before include "Manufacturer" , "Eg, factory owner" , "Ford, perhaps" , "Manufacturing chief" , "one's concern great?" .)