Gaa may refer to:
Compounds Glacial (water-free), acetic acid Acid alpha-glucosidase, also known as glucosidase, alpha; acid, an enzyme a codon for glutamic acid
Government GADA 601, Argentine Army unit Grupo de Artillería Antiaérea 601 (Anti-Aircraft Artillery Group 601) General Allotment Act, US law passed in 1887 regarding Indian land Group Areas Acts, South African apartheid laws General Appropriation Act, the legislative act used in some countries for a national or state budget
Organisations Gaelic Athletic Association, governing body of Gaelic games such as hurling and Gaelic football Gay Activists Alliance, New York City gay rights organisation 1969–81 Gemmological Association of Australia, an educational organisation based in Sydney Global Accounting Alliance, an accounting organisation Global Aquaculture Alliance, an international non-profit trade association Grenada Athletic Association, the governing body for the sport of athletics in Grenada Guam Adventist Academy, a private school in Guam
Other uses Gaa language, a language of Nigeria Ga'a, a military leader in the ancient Oyo Empire in West Africa gaa, the ISO 639 code for the Ga language of Ghana GAA, the ICAO airline code for Business Express Airlines Gaelic football, an Irish team sport commonly known as GAA Generic Authentication Architecture, a mobile phone specification Goals against average, goalkeeping statistic used by several sports and many leagues Ford GAA engine Gate-all-around, a specific type of 3D transistors