set sth (off) against sth
phrasal verbwithsetverbuk/set/ussetting|set|set
ACCOUNTING
to use orrecordone thing,especiallythecostof something, inordertoreduceorremovetheeffectof another:
Costs of newequipmentormachinery, such as acomputer, can also beset againsttax.
Therulesdo notallowsurplusesoverbookvaluein otherpartsof thebusinessto be set off againstreductionselsewhere.