Exact retribution for destruction of Geneva (6)
I believe the answer is:
avenge
'exact retribution' is the definition.
(I've seen this before)
'destruction of geneva' is the wordplay.
'destruction of' indicates anagramming the letters.
'geneva' anagrammed gives 'AVENGE'.
'for' acts as a link.
(Other definitions for avenge that I've seen before include "Get satisfaction for wrong done" , "Get even" , "Inflict harm in return (for wrong)" , "Inflict retribution" , "Retaliate on behalf of" .)