| Acronym | Definition |
|---|
| APEX | Atacama Pathfinder Experiment |
| APEX | Accepted Practices Exchange (Convention Industry Council initiative) |
| APEX | Association of Professional Executives of the Public Service of Canada (l'Association Professionelle des Cadres de la Fonction Publique du Canada) |
| APEX | Advance Purchase Excursion (airline industry) |
| APEX | Application Executive |
| APEX | Agência de Promoção às Exportações |
| APEX | Airborne Prism Experiment (hyperspectral pushbroom spectrometer) |
| APEX | Additive System of Photographic Exposure |
| APeX | Albany Power Exchange |
| APEX | Association of Professional Executive, Clerical and Computer Staff (UK union founded in 1989 and merged into GMU known as Britain's General Union) |
| APEX | Advanced Power EXtraction |
| APEX | Advanced Packet Exchange |
| APEX | Adaptive Principal component EXtraction (neural algorithm) |
| APEX | American Product Excellence |
| APEX | Automatic Preferred Enhanced Capital Securities (Goldman Sachs; hybrid debt equity secuirty) |
| APEX | Advanced Placement Experience |
| APEX | Advanced Plant Experiment |
| APEX | Armor Piercing Explosive (ammunition type) |
| APEX | All-Purpose Excuse :-) |
| APEX | Adaptive Planning and Execution (US DoD) |
| APEX | Arctic Polynya Experiment |
| APEX | Air Pollution Exchange |
| APEX | Advanced Prototyping, Engineering & eXperimentation (US Army Modeling and Simulation Laboratory - Redstone Arsenal, AL) |
| APEX | AntiProton Experiment |
| APEX | American Philatelic Society Expertising Service |
| APEX | Advanced Phase-conjugation Experiment |
| APEX | APLE Prototype Experiment |
| APEX | Argonne Production, Expansion and Exchange (model for electrical systems) |
| APEX | Academic Program for the Exceptional (Shelby County School System; Tennessee) |
| APEX | Advanced Photovoltaic & Electronics Experiment |
| APEX | Aerodynamic Performance Experiment |
| APEX | Automated Planning and Execution Control System |
| APEX | AIDS Peer Education Exchange (Gig Harbor, WA) |
| APEX | Active Plasma Experiment Satellite |
| APEX | Arctic Pulse Experimental (Sonar) |
| APEX | Automated Power Expert |
| APEX | Acquisition Planning and Execution |
| APEX | Argonne Plasma Experiment |
| APEX | African-American Panoramic Experience (Atlanta, Georgia) |
| APEX | Awards for Publication Excellence |
| APEX | Application Exchange |
| APEX | Asia-Pacific Environmental Exchange |
| APEX | Asian Professional Exchange |
| APEX | Advance Purchase Excursion Fare (Airline Lingo) |