CMK may refer to: Central Milton Keynes, the central business district of Milton Keynes, Buckinghamshire, England Centralna Magistrala Kolejowa, a long railway line in Poland cmk, an extinct Chemakum language once spoken by the Chemakum (ISO 639:cmk) Croron Mein Khel, a Pakistani gameshow aired on BOL Entertainment Crabbet/Maynesboro/Kellogg, a label for specific lines of "Domestic" or "American-bred" Arabian horses