GBO may refer to: Game Boy Original, a Nintendo handheld game console Gbo language (ISO 639-3: agb), a Cross River language of Nigeria Get Britain Out, a British Eurosceptic organisation The Graham Bond Organisation, a British music group Green Bank Observatory, a radio astronomy observatory in Green Bank, West Virginia Northern Grebo language (ISO 639-3: gbo), a Kru language of Liberia Nationality code of British Overseas Citizen in the machine-readable passport Growth buyout, a form of corporate acquisition