word | | Country name |
| conventional | Cayman Islands | conventional long form: none conventional short form: Cayman Islands |
| conventional | Central African Republic | conventional long form: Central African Republic conventional short form: none local long form: Republique Centrafricaine local short form: none former: Ubangi-Shari, Central African Empire abbreviation: CAR |
| conventional | Chad | conventional long form: Republic of Chad conventional short form: Chad local long form: Republique du Tchad/Jumhuriyat Tshad local short form: Tchad/Tshad |
| conventional | Chile | conventional long form: Republic of Chile conventional short form: Chile local long form: Republica de Chile local short form: Chile |
| conventional | China | conventional long form: People's Republic of China conventional short form: China local long form: Zhonghua Renmin Gongheguo local short form: Zhongguo abbreviation: PRC |
| conventional | Christmas Island | conventional long form: Territory of Christmas Island conventional short form: Christmas Island |
| conventional | Clipperton Island | conventional long form: none conventional short form: Clipperton Island local long form: none local short form: Ile Clipperton former: sometimes called Ile de la Passion |
| conventional | Cocos (Keeling) Islands | conventional long form: Territory of Cocos (Keeling) Islands conventional short form: Cocos (Keeling) Islands |
| conventional | Colombia | conventional long form: Republic of Colombia conventional short form: Colombia local long form: Republica de Colombia local short form: Colombia |
| conventional | Comoros | conventional long form: Union of the Comoros conventional short form: Comoros local long form: Union des Comores local short form: Comores |