| Acronym | Definition |
|---|
| GCI | Ground Circuit Interrupter |
| GCI | Getty Conservation Institute |
| GCI | Green Cross International (non-profit international environmental organization) |
| GCI | Gminne Centrum Informacji (Polish: Local Information Center) |
| GCI | Ground Controlled Interception (air defense tactic) |
| GCI | Global Class Identifier |
| GCI | Global Code Identifier |
| GCI | Ground Control Intercept (US DoD) |
| GCI | Global Commerce Initiative |
| GCI | Green Campus Initiative (various schools) |
| GCI | Growth Competitiveness Index |
| GCI | Great Cities Institute |
| GCI | Global Commons Institute (UK) |
| GCI | Glial Cytoplasmic Inclusion (neurology) |
| GCI | Générale Continentale Investissements (French: Continental General Investments) |
| GCI | Guitar Center, Inc. (Delaware) |
| GCI | Great Coasters International (Sunbury, PA) |
| GCI | Glen Canyon Institute (Salt Lake City, UT) |
| GCI | Golf Course Irrigation |
| GCI | Global Consultants Inc |
| GCI | Garbage Collection Interval |
| GCI | Gwich'in Council International (Alaska and Canada) |
| GCI | Group Critical Illness (insurance) |
| GCI | Gestion Credit Interentreprises (French: Intercompany Credit Management) |
| GCI | Groupe de Cardiologie Interventionnelle (French: Group of Interventional Cardiology) |
| GCI | Génie Civil Industriel (French: Industrial Engineering) |
| GCI | Group Crisis Intervention (various organizations) |
| GCI | Graduate Careers Ireland |
| GCI | Gray Card Index |
| GCI | Groupement des Croiseurs d'Iroise (French sailing club) |
| GCI | Gymnastiska Centralinstitutet (Sweden) |
| GCI | Green Communities Initiative (various locations) |
| GCI | Global Change Institute |
| GCI | General Components, Inc. (various locations) |
| GCI | Generalized Conversational Implicature |
| GCI | Grace Churches International |
| GCI | Gunei Chemical Industry (Japan) |
| GCI | Grupo Cristiano Interliceano (Spanish Christian group) |
| GCI | Groupe Central Immobilier (French: Central Real Estate Group) |
| GCI | Grace Communion International (formerly Worldwide Church of God) |
| GCI | Georgia Correctional Industries |
| GCI | Global Communication Infrastructure |
| GCI | Generix Collaborative Infrastructure (France) |
| GCI | Guernsey, Channel Islands, United Kingdom - Guernsey (Airport Code) |
| GCI | General Conditions of Insurance (various organizations) |
| GCI | Great Cranberry Island (Maine, USA) |
| GCI | Gascogne Comminges Immobilier (French: Comminges Gascony Estate) |
| GCI | Globalization Challenge Initiative (est. 1998) |
| GCI | Groupement des Coursiers Indépendants (French: Independent Group of Couriers) |
| GCI | Galt Collegiate Institute (Cambridge, Ontario) |
| GCI | Government Centre for Informatics (est. 1993; Slovenia) |
| GCI | Grey Communications International |
| GCI | General Communication Incorporated |
| GCI | Guild of Calamitous Intent (fiction, Venture Bros.) |
| GCI | Genetics Citation Index |
| GCI | Guides to Canadian Industry |
| GCI | Gross Cash Invested |
| GCI | Glenlawn Collegiate Institute |
| GCI | Geocentric Celestial Inertial Coordinate System |
| GCI | Generic Channel Interface |
| GCI | General Consumer Interest |
| GCI | Generic Communications Index |
| GCI | Global Cyber Investment (Japan) |
| GCI | Global Change Initiative |
| GCI | Gaussian Co-Channel Interferer |
| GCI | Gateway Customer Interface |
| GCI | Grade Crossing Inventory |
| GCI | Global Capital Investors LP |
| GCI | Guerra Consulting Inc (Overland Park, KS) |