Rare slip ruined counterattack (8)
I believe the answer is:
reprisal
'counterattack' is the definition.
(I've seen this before)
'rare slip ruined' is the wordplay.
'ruined' indicates anagramming the letters.
'rare'+'slip'='rareslip'
'rareslip' is an anagram of 'REPRISAL'.
(Other definitions for reprisal that I've seen before include "Counterattack" , "Tit for tat" , "Act of retaliation or vengeance" , "Retaliatory deed" , "Retaliation for an injury" .)