MCI

MCI may refer to:

Companies

 * MCI Communications, originally Microwave Communications Inc., the corporation that operated as MCI from 1963 to 1998
 * MCI Inc., formerly called WorldCom, which acquired MCI Communications, and was later acquired by Verizon Communications
 * MCI Group, a global event, association management and congress management company
 * Mobile Telecommunication Company of Iran, the largest mobile phone operator in Iran
 * Motor Coach Industries, a coach/bus manufacturing company
 * Music Center Incorporated, later known as Music Consultants Incorporated, a company that manufactured multi-track audiotape recorders and mixing consoles for professional studio recording
 * Music Collection International, the music division of Video Collection International
 * MCI, Frank Farian's record label

Education

 * Maine Central Institute, a boarding school in Maine, US
 * Marine Corps Institute, a coursework of Marine Corps education and training programs
 * Martingrove Collegiate Institute, a secondary school located in Toronto, Ontario, Canada
 * MCI Management Center Innsbruck, a privately organized business school in Innsbruck, Austria
 * Medical Council of India, a statutory body regulating medical education in India
 * Mennonite Collegiate Institute, a private, religious school in the town of Gretna, in Southern Manitoba
 * Middlefield Collegiate Institute, a secondary school located in Markham, Ontario, Canada
 * Museum Conservation Institute, of the Smithsonian Institution

Other organisations

 * Ministry of Communications and Information, a ministry of the Government of Singapore
 * Motek Cultural Initiative, a Toronto-based nonprofit organization promoting Israeli music and culture

Science and technology

 * Millicurie (mCi), 1/1000 of a curie, a non-SI unit of radioactivity
 * Megacurie (MCi), 1,000,000 times a curie, a non-SI unit of radioactivity
 * Macroinvertebrate Community Index, an index where the presence or lack of macroinvertebrates is used for monitoring stream health in New Zealand
 * Magnetic current imaging, using a scanning SQUID microscope
 * Malicious caller identification, a type of enhanced telephone service
 * Mass-casualty incident, a medical emergency involving more patients than can be easily handled by the crews initially assigned to the incident
 * Media Control Interface, an API for controlling multimedia peripherals connected to a Microsoft Windows or OS/2 computer
 * Meta-circular evaluator, in computing
 * Mild cognitive impairment, a neurological affliction often associated with Alzheimer's disease
 * Modulation contrast imaging, a term related to optical transfer function

Arts, entertainment, and media

 * MasterChef Indonesia, an Indonesian televised cooking competition

Other uses

 * 1101 in Roman numerals
 * Kansas City International Airport (IATA airport code), Kansas City, Missouri, US
 * Meal, Combat, Individual ration, the successor to the US Army C-ration
 * Michigan City station (Amtrak station code), Indiana, US
 * Miss Chinese International Pageant, an annual pageant for international women of Chinese descent
 * Monetary conditions index, a macroeconomic index number relevant for monetary policy
 * Short name for Manchester City F.C.