| Abbreviation | Definition |
|---|---|
| ODI | Office of Defense Intelligence |
| OECD | Organization for Economic Cooperation and Development |
| OEM | Original Equipment Manufacturer |
| OFTS | Office of Forensic Toxicology Services |
| OG | OutGoing |
| OK | Object Kill |
| OLEC | Office of Law Enforcement Coordination |
| OLEO | Office of Law Enforcement Operations |
| OLER | Office of Law Enforcement Requirements |
| OLES | Office of Law Enforcement Standards |
| OLET | Office of Law Enforcement Training |
| OM | Omaha Field Office |
| OO | Office of Origin |
| OOJ | Obstruction Of Justice |
| OP | Office of Preference |
| OPE | Office of Planning and Evaluation |
| OPO | Old Post Office |
| OPR | Office of Professional Responsibility |
| ORC | Organized Retail Crime |
| ORI | ORIginating agency |