term:

Offset

offset n

: a claim or amount that reduces or balances another claim or amount
: set-off [the creditor's own debt was an ]
;also
: the reduction or balance achieved by such a claim
[ȯf-set] vt : to balance, reduce, or calculate by reference to another amount [ the debt against a credit]

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.