| Akronim | Penjelasan |
| O |
| O | [kimia] Oxygen (Oksigen). |
| Ob. | [kitab injil] Obaja (Obadiah). |
| Oba. | [kitab injil] Obadiah (Obaja). |
| OC | Officer's Check (house bill). |
| OCPD | Officer-in-Charge of Police District. |
| Oct. | October (Oktober). |
| OD | Overdose, Overdraft (banking), Overdrawn. |
| ODA | Official Development Assistance. |
| OECD | Organisation for Economic Cooperation and Development (Pertubuhan Kerjasama dan Pembangunan Ekonomi). |
| OEM | Original Equipment Manufacturer. |
| Ogo. | Ogos (August). |
| OHQs | Operational HeadQuarters (Ibu Pejabat Operasi). |
| OIC | Organization of the Islamic Conference (Pertubuhan Persidangan Islam). |
| Okt. | Oktober (October). |
| OPEC | Organization of Petroleum Exporting Countries (Pertubuhan Negara-negara Pengeksport Minyak). |
| OPP | Other People's Property, Outline Perspective Plan. |
| OPP3 | Third Outline Perspective Plan. |
| OPR | Overnight Policy Rate (Kadar Dasar Semalaman). |
| OS | Operating System. |
| Os | [kimia] Osmium (Osmium). |
| OSA | Official Secrets Act. |
| OT | Overtime. |
| OUG | Overseas Union Garden. |
| oz. | ounce (auns). |
