- CA – Computer Associates was founded in 1976 as Computer Associates International, Inc. by Charles Wang
- C&A – named after the brothers Clemens and August Brenninkmeijer, who founded a textile company called C&A in the Netherlands in 1841.
- Cadillac – named after the 18th century French explorer Antoine Laumet de La Mothe, sieur de Cadillac, founder of Detroit, Michigan. Cadillac is a small town in the South of France. The company, founded in 1902, was purchased by General Motors in 1909 and survives to this day as a GM brand.
- CAE – originally Canadian Aviation Electronics
- Campagnolo – from the name of its founder, Tullio Campagnolo.
- Canon – Originally (1933) Precision Optical Instruments Laboratory the new name (1935) derived from the name of the company's first camera, the Kwanon, in turn named after the Japanese name of the Buddhist bodhisattva of mercy.
- Capcom - Capsule Computers
- Caprabo – Catalan supermarkets, founded by Pere Carbó, Jaume Prats and Josep Bonet.
- Carrefour – chain of supermarkets and hypermarkets which started with a store near a crossroads (carrefour in French) in Annecy.
- Caterpillar – Originally Holt Tractor Co, merged with Best Tractor Co. in 1925. A company photographer exclaimed aloud of a Holt tractor that the tracks' movement resembled a caterpillar moving along the ground. The name stuck.
- Cathay Pacific Airways Limited – The airline was founded on 24 September 1946 by American Roy C. Farrell and Australian Sydney H. de Kantzow, with each man putting up HK$1 to register the airline. They named it Cathay Pacific because Cathay was the ancient name given to China; and Pacific because Farrell speculated that they would one day fly across the Pacific.
- Casio – from the name of its founder, Kashio Tadao, who had set up the company Kashio Seisakujo as a subcontractor factory.
- CBS – Columbia Broadcasting System
- CDAC – Centre for Development of Advanced Computing, a government of India company.
- Celera – inspired by ‘celerity’ or swiftness (in decoding the human genome), with "era of the cell" a secondary meaning.
- Cemex – portmanteau of the company's former name of Cementos Mexicanos (Spanish for "Mexican Cement").
- Cenex – short for Central Exchange
- CGI Group – from the first letters of Information Management Consultant in French (Conseillers en Gestion et Informatique).
- Chevrolet – named after company co-founder Louis Chevrolet, a Swiss-born auto racer. The company was merged into General Motors in 1917 and survives only as a brand name.
- Chello – a Dutch internet service provider, its name was originally pronounced 'say hello' (in Dutch the letter C at the beginning of a word is pronounced 'say'). This did not catch on and now it is pronounced "cello" (as in the stringed instrument).
- Chrysler – named after the company founder, Walter P. Chrysler.
- Ciba Geigy – CIBA, named from Chemical Industry Basel (after Basel in Switzerland), merged with a company named after its founder Johann Rudolf Geigy-Merian. It became Novartis (below) after a merger with Sandoz.
- CiCi's Pizza – from the first letters of the last names of the founders of the franchise (Joe Croce and Mike Cole).
- Cigna – CIGNA was formed in 1982 through the combination of Insurance Company of North America (INA) and Connecticut General (CG). The name is combination of the letters of the predecessor companies, CG and INA.
- Cincom – originally called United Computer Systems, which was similar to several other software and services companies of the day. Two of the three founders visited Philco (Philadelphia Company), and this inspired them to create a new company name derived from Cincinnati (where it was based) and Computer (its business).
- Cisco – short for San Francisco.
- Citroën – named after André-Gustave Citroën (1878–1935), a French entrepreneur of Dutch descent. He was the fifth and last child of the Dutch Jewish diamond merchant Levie Citroen and Mazra Kleinmann (of Warsaw, Poland). The Citroen family moved to Paris from Amsterdam in 1873 where the name changed to Citroën.
- CKX, Inc. – named from "Content is King", with the X from founder Robert F.X. Sillerman. Other Sillerman companies include SFX Entertainment and FXM Asset Management.
- Clarion – named after the "bugle-like wind instrument used in ancient Greece," says the company, which wanted a name English speakers would find easy to remember. It was founded in Japan in 1940 as Hakusan Wireless Electric Company, making radios, and became Teikoku Dempa after merging with Takizawa Wireless Electric Industries in 1943.
- Coca-Cola – derived from the coca leaves and kola nuts used as flavoring. Coca-Cola creator John S. Pemberton changed the 'K' of kola to 'C' to make the name look better.
- Coleco – began as the Connecticut Leather Company.
- Colgate-Palmolive – formed from a merger of soap manufacturers Colgate & Company and Palmolive-Peet. Peet was dropped in 1953. Colgate was named after William Colgate, an English immigrant, who set up a starch, soap and candle business in New York City in 1806. Palmolive was named for the two oils (Palm and Olive) used in its manufacture.
- COLT – from City Of London Telecom
- Comcast – from communications and broadcast.
- Compaq – from computer and "pack" to denote a small integral object; or: Compatibility And Quality; or: from the company's first product, the very compact Compaq Portable.
- COMSAT – a contraction of communications satellites. This American digital telecommunications and satellite company was founded during the era of U.S. President John F. Kennedy era to develop the technology.
- ConocoPhillips – formed from the merger of Conoco (from Continental Oil Company) and the Phillips Petroleum Company.
- Copersucar – Brazilian production cooperative in sugar and alcohol, its name is a contraction of Cooperativa de Açucar e Álcool.
- Corel – from Cowpland Research Laboratory, after the name of the company's founder, Dr. Michael Cowpland.
- Cosworth – automotive engineering company named after company founders Mike Costin and Keith Duckworth.
- CPFL – Companhia Paulista de Força e Luz (São Paulo Company of Light and Power), one of the largest in Brazil, based in Campinas.
- Crabtree & Evelyn – toiletry company named after gardener John Evelyn, and the tree that bears Crabapples
- Cray – supercomputer company named after its founder, Seymour Cray.
- CRC Press – originally Chemical Rubber Company
- Cromemco – early microcomputer company in Silicon Valley (circa 1975–198?) founded by two PhD students who once lived at Stanford University's Crothers Memorial Hall (a dormitory).
- Cutco – Cooking Utensils Company.
- CVS – originally Consumer Value Stores. CEO Tom Ryan has said he now considers 'CVS' to stand for "Customer, Value, and Service".
Read more about this topic: List Of Company Name Etymologies