lender of last resort
From Longman Business Dictionarylender of last resortˌlender of ˌlast reˈsort noun (plural lenders of last resort) [countable]BANKING the central bank of a country which is responsible for controlling the banking system. It is considered as a lender for other banks only when there is no other organization to borrow fromThe Federal Reserve is a lender of last resort, and banks generally avoid borrowing from it except in extraordinary circumstances.