From Longman Dictionary of Contemporary Englishcarbon creditˌcarbon ˈcredit noun [countable usually plural] permission to produce a particular amount of carbon dioxide, which companies can buy and sell as a way of reducing harm to the environmentFrom Longman Business Dictionarycarbon creditˈcarbon ˌcredit noun [countable] COMMERCEa fixed amount of harmful gases such as carbon dioxide, that a company is allowed to send into the earth’s atmosphereElectricity companies are allocated less carbon credits than they need, in order to encourage investment in environmentally-friendly power generation.