| Abbreviation | Definition |
|---|---|
| OSCM | erations Specialist Master Chief Petty Officer |
| OSCM | Operations Specialist Master Chief Petty Officer |
| OSCS | erations Specialist Senior Chief Petty Officer |
| OSCS | Operations Specialist Senior Chief Petty Officer |
| OSSA | erations Specialist Seaman Apprentice |
| OSSA | Operations Specialist Seaman Apprentice |
| OSSN | erations Specialist Seaman |
| OSSN | Operations Specialist Seaman |
| OSSR | erations Specialist Seaman Recruit |
| OSSR | Operations Specialist Seaman Recruit |
| OSTD | ficer's Steward |
| OSTD | Officer's Steward |
| OT1 | ean Systems Technician Petty Officer 1st Class |
| OT1 | Ocean Systems Technician Petty Officer 1st Class |
| OT2 | ean Systems Technician Petty Officer 2nd Class |
| OT2 | Ocean Systems Technician Petty Officer 2nd Class |
| OT3 | ean Systems Technician Petty Officer 3rd Class |
| OT3 | Ocean Systems Technician Petty Officer 3rd Class |
| OTA1 | ean Systems Technician (automatic) Petty Officer 1st Class |
| OTA1 | Ocean Systems Technician (automatic) Petty Officer 1st Class |