Grey's Anatomy, a comedy / medical drama television series running since 2005.

Gabon (ISO 3166-1 alpha-2 code: GA), a nation in west central Africa

Georgia (U.S. state) (U. S. postal symbol: GA), a Southern U.S. state

Irish language (ISO 639-1: ga), or Gaeilge, the original language of Ireland

Genetic algorithm, an optimization technique in computer science

Girls Aloud, a British pop group created from the talent show Popstars: The Rivals

Gallium (Ga), the element of atomic number 31

Garuda Indonesia (IATA designator: GA), the national airline of Indonesia

General Availability, the final software development stage

United Nations General Assembly, the main deliberative organ of the United Nations

Galaxy Angel, a 2001 animated television series with an associated game and manga

General authority, a governing body of approximately 100 men in The Church of Jesus Christ of Latter-day Saints (Mormon church)

Ga-ga or Gaga ball, a form of dodgeball that is thought to have originated in Israel

General American, an accent of the Midwestern USA

Germantown Academy, the oldest nonsectarian day school in the United States

Gamblers Anonymous, a support group for recovering gamblers

Tabun (nerve agent) (NATO designation: GA), the first nerve agent chemical weapon to be discovered

General anaesthesia

Giga-ampere or Gigampere, an SI unit of electric current (equals 1,000,000,000 A)

Ga language, the language spoken by the Ga people

G. A. Kulkarni (1923-1987), an Indian author

Ga people, an ethnic group of Ghana

Google Analytics, a free service offered by Google that generates detailed statistics about the visitors to a website.

General Atomics, an American nuclear physics and defense contractor

Gridiron Australia, national sporting body for American Football in Australia.

General aviation, the category of civil aviation encompassing all non-scheduled aircraft flights

Gibberellic Acid, a plant growth hormone

General Assistance Governmental aid frequently issued to homeless and mental-health patients, for temporary and long-term assistance.

Georgia Railroad and Banking Company (AAR mark: GA), a railroad in (American) Georgia that has since merged with CSX.

Greening Australia, an Australian conservation organization.

General assembly, an official session of the members of a union, church, association, or similar organization

Gauge, an engineering term with various meanings

Genetic Alliance, a coalition of more than 600 advocacy organizations

Geographical Association, a UK organisation dedicated to the teaching of geography

Geoscience Australia, a geoscience agency of the Australian government

Gaga, a type of Caribbean music, especially known in Haiti

Ga District, Ghana, a former district of southern Ghana

Groove Armada, an electronic music group from the UK.