Wrong pace after retirement (4)
I believe the answer is:
tort
'wrong' is the definition.
(legal term)
'pace after retirement' is the wordplay.
'pace' becomes 'trot' (I've seen this in another clue).
'after retirement' says the letters should be written backwards.
'trot' reversed gives 'TORT'.
(Other definitions for tort that I've seen before include "Private wrong for which damages may be claimed" , "A private or civil wrong that may attract damages" , "Legal wrong or injury" , "Private or civil wrong - trot after it" , "Trot to get legal wrong" .)