Showing unoriginality in making black-hearted profit (5)

I believe the answer is:

again

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'showing unoriginality in making black-hearted profit' is the definition.
I can't judge whether this definition defines the answer.

'black-hearted profit' is the wordplay.
'hearted' says to take the centre.
'profit' becomes 'gain' (synonyms).
The middle letter of 'black' is 'a'.
'a'+'gain'='AGAIN'

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(Other definitions for again that I've seen before include "return" , "Moreover - a second time" , "One more time, encore" , "'Another time, once more (5)'" , "second term" .)

I've seen this clue in the Evening Standard.

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