| Abbreviation | Definition |
|---|---|
| OTBD | Outboard |
| OTC | Orbiter Test Conductor |
| OTD | Operational Technical Documentation |
| OTD | Orbiter Test Director |
| OTDA | Office of Tracking and Data Acquisition (now OSTDS) |
| OTEMP | Overtemperature |
| OTF | Out Too Far |
| OTH | Over-the-Horizon (Radar) |
| OTIS | On Time In Spec |
| OTK | Oxidizer Tank |
| OTL | Ordnance Test Laboratory |
| OTLC | Orbiter Timeline Constraints |
| OTM | Office of Telecommunications Management |
| OTO | One-Time-Only |
| OTOS | Orbit-to-Orbit Stage |
| OTP | Operational Test Procedure |
| OTP | Operations Test Plan |
| OTP | Operations Turnaround Plan |
| OTR | Operating Time Record |
| OTR | Outer |