emission credit

(also emissions credit)

noun [C, usually plural] (also pollution credit, also US emission reduction credit) ENVIRONMENT

Definition

› a reduction in pollution that is equal to one emission unit. A company that reduces its pollution can sell its emission credits to companies that fail to reduce their pollution: If a company fails to meet its emission-reduction target, it will need to buy additional emission credits to cover its excess emissions.

(Definition of emission credit noun from the Cambridge Business English Dictionary © Cambridge University Press)