Cruel way to make a profit (5)
I believe the answer is:
lucre
'a profit' is the definition.
(I know that profit can be written as lucre)
'cruel way' is the wordplay.
'way' indicates an anagram (another way of arranging the letters).
'cruel' with letters rearranged gives 'LUCRE'.
'to make' acts as a link.
(Other definitions for lucre that I've seen before include "Wealth - cruel (anag)" , "Sordid gain; riches" , "Cash" , "(Filthy) profit" , "There's money" .)