MCA

Science and technology

Minimum crossing altitude, a minimum obstacle crossing altitude for fixes on published airways
Medium Combat Aircraft, a 5th generation fighter aircraft in India's HAL AMCA (Advanced Medium Combat Aircraft) program
Macenta Airport, Guinea (by IATA code)
Ministry of Civil Aviation (United Kingdom) from 1941 to 1953

MacConkey agar, a selective growth medium for bacteria
Monochloroacetic acid, carboxylic acid, manufactured by chlorinating acetic acid
Methylcholanthrene, a carcinogen
Methyl cyanoacrylate, an organic compound
Metabolic control analysis, analysing how the control of fluxes and intermediate concentrations in a metabolic pathway is distributed
Middle cerebral artery, one of the three major blood supplies to the brain

Medieval Climatic Anomaly (Medieval Warm Period, also Medieval Climate Optimum), a notably warm climatic period in the North Atlantic region from about 950 to 1250.

Machine Check Architecture, a method for a CPU to report hardware errors to an operating system
Maximum credible accident, a postulated scenario that a nuclear facility must be able to withstand
Micro Channel architecture, a type of computer bus
Mitsubishi MCA, an emissions control approach for gasoline-powered vehicles during the 1970s
Movable cellular automaton
Multichannel analyzer, instrument recording pulse counts at a range of (esp. photon energy) levels

MCA Inc., a now defunct company (originally called Music Corporation of America) and its subsidiary companies:
- MCA Records
- MCA Nashville Records
- MCA Home Video, former name of Universal Pictures Home Entertainment
- MCA Music Inc. (Philippines), a Philippine branch of Universal Music Group which uses the MCA brand due to a trademark issue
Maubeuge Construction Automobile (MCA), a subsidiary of French car manufacturer Renault
Minato Communications Association, a former company name of the Japan Electronics and Information Technology Industries Association

Malaysian Chinese Association, a political party in Malaysia
Maritime and Coastguard Agency, an agency of the United Kingdom Government
Medicines Control Agency, which merged with the Medical Devices Agency to become the Medicines and Healthcare products Regulatory Agency in the UK
Millennium Challenge Account, a U.S. program for aid to developing countries
Ministry of Corporate Affairs, an Indian government ministry

Maharashtra Chess Association
Medal Collectors of America
Metal Construction Association
Metropolitan Church Association, Methodist denomination in the holiness movement
Minerals Council of Australia
MotorCoach Australia
Multicore Association, an industry association regrouping companies and universities interested in multicore computing research
Mumbai Cricket Association, ruling body for cricket in Mumbai
Museum of Contemporary Art (disambiguation), numerous museums around the world
Music Council of Australia, former peak body for music in Australia (1993–2020)

Master in Customs Administration, a trade-related graduate degree offered in PMI Colleges in the Philippines
Master of Computer Applications, a postgraduate degree in computer science offered in India

Marist College Ashgrove, an Australian School
McIntosh County Academy, a high school in McIntosh County, Georgia, United States
Memphis College of Art, an art school in Tennessee, United States
Morrison Christian Academy, an American school in Taiwan

Depository Institutions Deregulation and Monetary Control Act, a US financial statute passed in 1980
Mental Capacity Act 2005, an Act of the Parliament of the United Kingdom applying to England and Wales
Military Commissions Act of 2006, US legislation