Money initially invested in pole dancing put to unknown use (6)
I believe the answer is:
employ
'use' is the definition.
(I know that exploit is a is a more specific form of the action of use)
'money initially invested in pole dancing put to unknown' is the wordplay.
'initially' says to take the initial letters.
'invested in' is an insertion indicator.
'dancing' is an anagram indicator.
'put' means one lot of letters go next to another.
'to unknown' becomes 'y' (algebra).
The initial letter of 'money' is 'm'.
'pole' anagrammed gives 'eplo'.
'm' placed within 'eplo' is 'emplo'.
'emplo'+'y'='EMPLOY'
(Other definitions for employ that I've seen before include "Draw on" , "Take on - recruit" , "Put on the payroll" , "Take on (staff)" , "Keep (someone) occupied" .)