CLN may refer to: Computing and technology Class Library for Numbers, a free software project Computer Learning Network, a technical school (college) in Mechanicsburg, Pennsylvania; see YTI Career Institute Politics and government Certificate of Loss of Nationality, an American form National Liberation Committee (), the underground political entity of Italian Partisans during the German occupation of Italy Other Catamount Library Network, a library consortium in Vermont Chapeltown railway station, in South Yorkshire Credit-linked note, a security issued by a special purpose company or trust Sri Lanka's International Telecommunication Union abbreviation; see List of ITU letter codes See also Genes related to neuronal ceroid lipofuscinosis: CLN3, CLN5, CLN6, CLN8