CK

CK, Ck, or ck may refer to:

Science and technology

 * Conductive keratoplasty, a type of refractive surgery
 * Creatine kinase, an enzyme
 * Cytokinin, a plant hormone
 * Cytokeratin (CK1 to CK20), keratin proteins
 * Cyanogen chloride, an inorganic chemical

Computing

 * .ck, the Internet country code top-level domain for the Cook Islands
 * Collective Knowledge (software), a framework for collaborative and reproducible research

Organizations

 * Calvin Klein, a fashion company
 * Chowking, a Filipino fast food chain
 * Colombo Kings, a team participating in Lanka Premier League
 * CK Hutchison Holdings, a multinational conglomerate headquartered in Hong Kong
 * Bloods, a US-based street gang, from the nickname "Crip Killer"
 * Circle K, an international chain of convenience stores

Transportation

 * China Cargo Airlines (IATA code CK)
 * Composite Corridor, a designation of British Rail carriages
 * Chevrolet C/K, a model of pickup truck

People

 * Louis C.K. (born 1967), American comedian
 * Con Kolivas, Australian anaesthetist

Other uses

 * ck (digraph), a letter combination used in spelling
 * C-K theory (concept-knowledge theory), in design
 * CK (album), a 1988 album by Chaka Khan
 * Civilinis kodeksas, the Code of Lithuania
 * Core Knowledge, a textbook series
 * Cranbrook Kingswood, a school in the US