UAC may refer to: Computing User Account Control, a security feature in Microsoft Windows Session Initiation Protocol#User agent client Organizations Ulster Army Council, 1973 Northern Ireland loyalist paramilitary group Undeb Amaethwyr Cymru, the Farmer's Union of Wales Unemployment Action Center, a non-profit organization in New York City, US United Apostolic Church Union of Catholic Apostolate Université d’Abomey-Calavi, part of the National University of Benin United Africa Company, 20th-century British company United Africa Company of Nigeria, formerly a subsidiary of United Africa Company United Aircraft Corporation, Russian aerospace and defense company United Arab Command, of the Arab League Universities Admissions Centre, Australia Urban Appalachian Council, Cincinnati, US Other Unaccompanied Alien Children, United States government classification for children in immigration custody Unified Arab Code, a Civil Code produced by the Arab League between 1988 and 1996 Urban adult contemporary, radio music format Union Aerospace Corporation, fictional military contractor in the Doom video game franchise UAC, a codon for the amino acid tyrosine