Encyclopedias, Almanacs, Transcripts, and Maps
- continuation school
- continuing education
- contract bridge
- control surface
- Contucci, Andrea
- convector
- Convention on International Trade in Endangered Species of Wild Fauna and Flora
- convertiplane
- convolvulus
- Conway of Allington, William Martin Conway, 1st Baron
- Conway, Henry Seymour
- Conway, Sir Martin
- cony
- Cooch Behar
- Cook, Frederick Albert
- Cook, Mount
- Cook, Thomas
- Cooke, Terence James
- Cookeville
- Coolidge Dam