| Abbreviation | Definition |
|---|---|
| L | Left |
| L | Level |
| L | Low |
| L | Lumen |
| L&C | Laboratory and Checkout |
| L&D | Landing and Deceleration |
| L&L | Launch and Landing |
| L&S | Logistics and Support |
| L&T | Laboratory and Test |
| L/D | Length-to-Diameter ratio |
| L/D | Lift-to-Drag ratio |
| L/H | Local Horizontal |
| L/O | Lift-Off |
| L/S | Landing Site |
| L/S | Load System |
| L/T | Load Test |
| La | Lanthanum |
| LA | Launch Abort |
| LA | Launch Aft |
| LA | Launch Area |