- 1 Cope's Paper Mill
- 5 Copies (derivative objects)
- 3 Copley, John Singleton, 1738-1815
- 2 Copper engravings (visual works)
- 1 Copper industry
- 1 Copper mining
- 2 Copperhead movement
- 1 Copper-mines of Agordo (Work of Art)
- 1 Coppersmiths
- 3 Copperwork
- 14 Coptic (culture or style)
- 1 Coptic (Orthodox Christianity)
- 1 Copybooks (instructional materials)
- 8 Copyright
- 3 Copyright infringement
- 1 Coral reef areas
- 1 Coral reefs
- 7 Coral Street
- 10 Corals (animals)
- 1 Corbin Cabinet Lock Co. (Firm)
- 1 Corbin Disinfectant Co.
- 1 Corbin, P&F (Firm)
- 1 Corinthian Basin
- 4 Corinthian Street
- 1 Cork
- 1 Cork Distilleries Company
- 1 Cork, Mary Boyle, Countess of, d. 1840
- 1 Corks (stoppers)
- 2 Corliss bevel gear cutter
- 4 Corliss Steam Engine Company
- 8 Corliss, George H. (George Henry), 1817-1888
- 13 Corn
- 8 Corn Exchange National Bank
- 6 Cornelius & Sons
- 1 Cornelius & Sons Brass Foundry
- 1 Cornelius and Baker Lighting Manufactory
- 3 Cornelius, Anne Brown
- 1 Cornelius, Saint, Pope
- 1 Cornell University
- 7 Cornerstone laying
