| Abbreviation | Definition |
|---|---|
| LEB | LASCO Electronics Box |
| LEB | Live Eclipse Broadcaster |
| LEB | Lower Equipment Bay |
| LEC | Lockheed Electronics Company |
| LED | Low Energy Detector |
| LEEF | Launch Equipment Exposure Facility |
| LEH | Launch/Entry Helmet |
| LEM | Laboratory Environment Model |
| LEM | Launch Escape Monitor |
| LEM | Lunar Entry Mode |
| LEM | Lunar Excursion Module |
| LENA | Low Energy Neutral Atom |
| LEND | Lunar Exploration Neutron Detector |
| LEOP | Launch and Early Orbit Phase |
| LEOS | Low Earth Orbiting Satellite |
| LER | Long Eye Relief |
| LER | Long Eye Relief (Optics) |
| LERC | Lewis Research Center |
| LeRC | Lewis Research Center (Cleveland, OH) |
| LES | Land Earth Station |