MCI
- 1101
- Curie (unit)
- Frank Farian
- Kansas City International Airport
- MCI (recording studio gear)
- MCI Communications
- MCI Inc.
- MCI Management Center Innsbruck
- Macroinvertebrate Community Index
- Maine Central Institute
- Malicious caller identification
- Malvern Collegiate Institute
- Manchester City F.C.
- Marine Corps Institute
- Martingrove Collegiate Institute
- Mass-casualty incident
- MasterChef Indonesia
- Meal, Combat, Individual ration
- Media Control Interface
- Medical Council of India
- Mennonite Collegiate Institute
- Meta-circular evaluator
- Methylchloroisothiazolinone
- Michigan City station
- Middlefield Collegiate Institute
- Mild cognitive impairment
- Ministry of Communications and Information
- Miss Chinese International Pageant
- Mobile Telecommunication Company of Iran
- Monetary conditions index
- Motek Cultural Initiative
- Motor Coach Industries
- Museum Conservation Institute
- Video Collection International