set-off

Concise Oxford English Dictionary © 2008 Oxford University Press:
set-off/ˈsɛtɒf/

▶noun

• 1 an item or amount set off against another.

  ■ Law a counterbalancing debt pleaded by the defendant in an action to recover money due.

  ■ dated a counterbalancing or compensating circumstance or condition.

• 2 a step or shoulder at which the thickness of part of a building or machine is reduced.

• 3 Printing the unwanted transference of ink from one printed sheet or page to another.