| Acronym | Definition |
|---|
| OCT | October |
| OCT | Ontario College of Teachers (Canada) |
| OCT | Office of Cable Television |
| OCT | Optical Coherence Tomography (medical imaging technique) |
| OCT | Octave |
| OCT | Officer Cadet (Singapore) |
| OCT | Octal |
| OCT | Office of Counter Terrorism (various locations) |
| OCT | Original Certificate of Title (Philippines) |
| OCT | Office Customization Tool (software) |
| OCT | Okinawa Cellular Telephone (Japan) |
| OCT | Optimal Control Theory |
| OCT | Object Class Table |
| OCT | Overseas Countries and Territories |
| OCT | Omnidirectional Control Technology |
| OCT | Object Code Translator |
| OCT | Output Control Transistor |
| OCT | Optimized Compensation Transactions |
| OCT | Ogaki Cable Television (Japan) |
| OCT | Octamer Binding Transcription Factor |
| OCT | Octamer-Binding Transcription Factor |
| OCT | Offset Catch Tray (photocopiers) |
| OCT | Official Conspiracy Theory |
| OCT | Oregon Cultural Trust |
| OCT | Ocular Coherence Tomography |
| OCT | Optimal Cutting Temperature (compound for fixing specimens prior to cryosectioning) |
| OCT | Office of Clinical Trials |
| OCT | Oita Cable Telecom (Japan) |
| OCT | Oxford Classical Texts |
| OCT | One Cool Tuna (fishing accessories brand) |
| OCT | Oxytocin Challenge Test |
| OCT | Optimized Compression Topology (audio) |
| OCT | Oral Contraceptive Therapy |
| OCT | Order Cycle Time |
| OCT | Organismo de Control Técnico (Spanish) |
| OCT | Outlook Configuration Tool (software) |
| OCT | Oak Cliff, Texas |
| OCT | Ocala Civic Theatre |
| OCT | Ocean Color and Temperature |
| OCT | Optical Current Transducer |
| OCT | Ontario Certified Teacher (Ontario College of Teachers; Canada) |
| OCT | Officina Città Torino (Italian) |
| OCT | Office, Chief of Transportation |
| OCT | OSHA Compliance Team |
| OCT | Optical Committee of Turkey |
| OCT | Optical Channel Trail |
| OCT | Operational Climatic Testing |
| OCT | Operations Concept Team |
| OCT | Ottawa City Transportation (Canada) |
| OCT | Oils and Fats Chemistry and Technology |
| OCT | Obligation-Certification Tree |