An offset can be defined as compensation required as a condition of purchase in either government-to-government or commercial sales of defence equipment and services to a government. They take the form of industrial, commercial and political arrangements under which suppliers implement specific projects aimed at partially or fully compensating (offsetting) the buyer's procurement costs.

a compensating equivalent

compensate for or counterbalance; "offset deposits and withdrawals"

a deduction or claim that serves to compensate for another claim, such as, "I promise to pay if the seller fixes the roof

a type of compensation involving industrial work in return for a defense-related purchase

1. Compensation. Counterbalance. 2. A change from one to two axes.