C12, C.XII or C-12 may be: LNER Class C12, a class of British 4-4-2T locomotives C12 Workmen's Compensation (Agriculture) Convention, 1921 C-12 Huron, a logistics support aircraft of the U.S. Military (military versions of the Beechcraft Super King Air) C-12 Vega, an early transport of the United States Army Air Corps Albatros C.XII, a World War I German military reconnaissance aircraft Autovia C-12, a highway in Catalonia, Spain Cierva C.12, a 1927 British experimental autogyro , a British C-class submarine of the Royal Navy JNR Class C12, a class of Japanese steam locomotive Sauber C12, a 1993 racing car Spyker C12 Zagato, a 2007 Dutch car , a light cruiser of the United States Navy C-12: Final Resistance, a video game for PlayStation Caldwell 12 (NGC 6945, the Fireworks Galaxy), an intermediate spiral galaxy in the constellations Cepheus and Cygnus The 12th century Carbon-12, the most abundant stable isotope of carbon Malignant neoplasm of piriform sinus ICD-10 code Bill C-12 in Canadian law