GMAC or G-MAC may refer to:

• Ally Financial (General Motors Acceptance Corporation), traded as GMAC until 2010
• GMAC Insurance, former name of National General Insurance
• GMAC Real Estate, a former real estate franchised brokerage firm
• GMAC ResCap (Residential Capital), which includes GMAC Mortgage
• Graduate Management Admission Council, an international association of business schools
• GMA Canada, the Gospel Music Association of Canada, formerly the CGMA
• Global Markets Advisory Committee, part of the U.S. Commodity Futures Trading Commission

• Galois Message Authentication Code, a type of cryptographic message authentication code
• Giga multiply–accumulate operations per second, a rate of multiply–accumulate operations
• Gigabit media access controller, for handling an Ethernet physical transceiver; See Gigabit Ethernet

• Graeme McDowell (born 1979), Northern Irish professional golfer nicknamed G-Mac
• GMAC Bowl, a sponsored game of college level American football, now known as the LendingTree Bowl
• Great Midwest Athletic Conference, a U.S. college athletic conference established in 2011 and starting competition in 2012
• GMAC ebike motor, a modified MAC hub motor sold by Grin Technologies

• GMAC massacre, a 1990 shooting by James Edward Pough in a car loan office in Florida, US

This disambiguation page lists articles associated with the title GMAC.
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