Heartless reprisal? Very true (4)
I believe the answer is:
real
'very true' is the definition.
'real' can be an answer for 'true' (similar in meaning). I'm not certain of the 'very' bit.
'heartless reprisal?' is the wordplay.
'heartless' suggests removing the centre.
'reprisal' with its middle removed is 'REAL'.
Can you help me to learn more?
(Other definitions for real that I've seen before include "True" , "Working together" , "Actual, not imagined" , "Genuine or existing" , "'Genuine, actual (4)'" .)