Fictional entities

• Mac (Green Wing), a television character
• Mac (It's Always Sunny in Philadelphia), a television character
• Mac Gargan, an enemy of Spider-Man
• Mac, a character on Foster's Home for Imaginary Friends
• Angus "Mac" MacGyver, from the television series MacGyver
• Cindy "Mac" Mackenzie, from the TV series Veronica Mars
• Lt. Col. Sarah MacKenzie, from the TV series JAG
• Dr. Terrence McAfferty, from Robert Muchamore's CHERUB and Henderson's Boys novel series
• Mac McAnnally, in The Dresden Files series
• Randle McMurphy, in the movie One Flew Over the Cuckoo's Nest
• Mac Taylor, from the TV series CSI: NY
• Mac, a canine character in the television series Clifford the Big Red Dog
• Monster Attack Crew, a fictional pilot squadron in the television series Ultraman Leo
• MAC (Mysterious Alien Creature), the titular character in the 1988 film Mac and Me
• Mac (Makrand Deendayal Chatpatiya), portrayed by Akshay Kumar in the 2005 Indian comedy film Garam Masala

Other arts and entertainment

• Mac (film), 1992, directed by and starring John Turturro
• Mac (novel), by John MacLean
• Mac the Moose , a public statue in Moose Jaw, Saskatchewan, Canada
• Mac, a Sports Beanie Baby cardinal produced by Ty, Inc. in 1999
• MAC Awards, for achievements in cabaret, comedy, and jazz, administered by the Manhattan Association of Cabarets & Clubs

Economics

• Marginal abatement cost, in environmental economics
• Material adverse change, a provision in mergers and acquisitions contracts and venture financing agreements

Businesses

• MAC Cosmetics, a cosmetics brand, stylized as M•A•C
• Mac Para Technology, a Czech aircraft manufacturer
• Macerich (NYSE stock symbol MAC), an American real estate investment trust
• Manufacture d'armes de Châtellerault, a French state arms manufacturer
• Martin's Air Charter, now Martinair, an airline
• Medicare Administrative Contractor, a private company contracted to administer Medicare benefits in the US
• Military Armament Corporation, former American small arms manufacturer
• Morgan Advanced Ceramics, a ceramics manufacturing company
• Money Access Card or Money Access Center, a former US ATM network

Government and military

• Mainland Affairs Council, an agency under the Executive Yuan of the Republic of China
• Merchant aircraft carrier, used during World War II by Britain and the Netherlands
• Metropolitan Airports Commission, the operator of airports in the Minneapolis-St. Paul area
• Military Affairs Commission in China; see Central Military Commission (China)
• Military Airlift Command, the predecessor of the Air Mobility Command of the United States Air Force
• Mission Assurance Category, a US Department of Defense engineering designation
• Mixed Armistice Commissions, a United Nations organization for monitoring Middle East ceasefires
• Modern Army Combatives, a hand-to-hand combat training regimen
• Municipal Assistance Corporation, created by the State of New York in 1975 to deal with New York City's fiscal crisis
• Convention on Mutual Administrative Assistance in Tax Matters, developed jointly between the OECD and Council of Europe

Non-profit

• mac (Birmingham), formerly the Midlands Arts Centre, in Birmingham, UK
• Malaysian AIDS Council
• Marine Aquarium Council
• Murphree Area Council
• Myanmar Accountancy Council

Politics

• Mouvement d'Action Civique , a defunct Belgian far right group
• Mudiad Amddiffyn Cymru , a Welsh organization responsible for several bombing incidents
• Muslims Against Crusades, a banned radical Islamist group in the UK

Names

• Mac (nickname)
• Mạc, a Vietnamese surname
• Mạc dynasty, 16th-century rulers in Vietnam

Individuals

• Mac (rapper) (born 1977), American rapper, stage name of McKinley Phipps Jr
• MC Mac, member and musician of So Solid Crew
• John McCarthy (conductor) (1916–2009), British conductor known as "John Mac" or just "Mac"
• Derek McCulloch (1897–1967), British radio broadcaster known as "Uncle Mac"
• Ian McCulloch (singer) (born 1959), referred to as "Mac the Mouth" or just "Mac"
• Stanley McMurtry (born 1936), British cartoonist with the pen name "Mac"

Museums and arts centers

• Costa Rican Museum of Art (Spanish : Museo de Arte Costarricense), Costa Rica
• mac, Birmingham (formerly Midlands Arts Centre), England
• Metropolitan Arts Centre, Belfast, UK
• Archaeology Museum of Catalonia (Spanish: Museu d'Arqueologia de Catalunya), Spain
• Niterói Contemporary Art Museum (Portuguese: Museu de Arte Contemporânea de Niterói), Brazil
• Museum of Contemporary Art of Lima (Spanish : Museo de Arte Contemporáneo), Peru

Other places

• Macau (ISO 3166 code: MAC), an administrative region of China
• Macaulay railway station, Melbourne, Australia
• UCLA Marina Aquatic Center, a recreational facility in Marina del Rey, California
• Macomb station (Amtrac station code: MAC), Illinois, US
• Mid-America Center, an arena and convention center in Council Bluffs, Iowa

Biology and medicine

• MAC (chemotherapy), a chemotherapy regimen of Mitoxantrone and Ara-C
• Maximum allowable concentration, a concept related to threshold limit value (TLV)
• Membrane attack complex, an immune system function using complement
• Microbiota-accessible carbohydrates, a category of carbohydrates consumed by gut microbes
• Minimum alveolar concentration, a measure used to compare the strengths of anesthetic vapors
• Mitochondrial apoptosis-induced channel, the cytochrome c release pore of apoptotic mitochondria
• Monitored anesthesia care, a form of anesthesia with partial awareness
• Mycobacterium avium complex, a group of environmental pathogens

Computing and telecommunication

• Mac (computer), a brand of computers and computer operating systems made by Apple Inc.
  • macOS, formerly Mac OS X and OS X, Apple's current operating system for Mac computers
  • Classic Mac OS, the original operating system for Apple's Macintosh
  • .Mac, now iCloud, a subscription service by Apple
• MAC times, metadata containing event times associated with a computer file
• Mandatory access control, a type of access control in computer security
• Maximum activate count, a parameter associated with the LPDDR4 memory's TRR feature
• Medium access control or media access control, a sublayer of the Data Link layer
  • MAC address, a unique identifier assigned to a network interface controller
• Message authentication code, used to authenticate a message in cryptography
• Migration Authorisation Code, used when switching Internet service providers in the UK
• Multiplexed Analogue Components, a proposed satellite television transmission standard
• Multiply–accumulate operation (MAC), or multiplier–accumulator, in digital signal processing
• .mac, a file extension for macros in Agilent ChemStation software

Other science and technology

• Mean aerodynamic chord, a measure of the geometry of an airfoil

Clubs and teams

• Maranhão Atlético Clube, a Brazilian association football club
• Marília Atlético Clube, a Brazilian association football club
• Missouri Athletic Club, a traditional gentlemen's and athletic club in downtown St. Louis, Missouri
• Multnomah Athletic Club, a private athletic club in Oregon

Conferences

Other sports

• MAC Award, in American college soccer, now merged into the Hermann Trophy