| Acronym | Meaning |
| OBL | Oblast (Russian, province; used in postal addresses) |
| OBL | Obligated |
| OBL | Office of Business Liaison |
| OBL | Operating Budget Ledger |
| OBL | Operation Babylift (Vietnam) |
| OBL | Optical Break Lock (missiles, object being observed or tracked leaves the field-of-view of the tracking system) |
| OBL | Osama Bin Laden (international terrorism sponsor) |
| OBL | Outside Battery Limits (scope of contract) |