| Abbreviation | Definition |
|---|---|
| NLCP | National Laboratory Certification Program |
| NLCP | Native Landscape Certification Program |
| NOCP | National Officials Certification Program |
| NOTCE | National Occupational Therapist Certification Examination |
| NOTCE | National Occupational Therapy Certification Examination |
| NRCC | National Registry of Certified Chemists |
| NTC | National Technical Certification |
| OCA | Oracle certified Associate |
| OCC | Osteopathic Continuous Certification |
| OCCEA | Organic Certification Clean Equipment Affidavit |
| OCE | Open Cut Examiner |
| OCF | Open Certification |
| OCF | Open Certification Framework |
| OCSA | OnBase Certified System Administrator |
| OCT | Ontario Certified Teacher |
| Oeko-tex | A textile certification |
| OGEL | Open General Export Licence |
| OSCS | Oregon Seed Certification Service |
| OTCP | Officials Training and Certification Program |
| PACC | Physician Assistants Certification Council |