The Collaborative International Dictionary of English v.0.48:

Recoupment \Re*coup"ment\ (-ment), n.
   The act of recouping.
   [1913 Webster]

   Note: Recoupment applies to equities growing out of the very
         affair from which thw principal demand arises, set-off
         to cross-demands which may be independent in origin.
         --Abbott.
         [1913 Webster]