| L | Lunar | - | Business and Finance |
| L-DEO | Lamont-Doherty Earth Observatory | - | Business and Finance |
| L2D2 | Lightweight LORAN Digital Dropsonde | - | Business and Finance |
| LA | Longmont Anticyclone | - | Business and Finance |
| LAC | Local Area Coverage | - | Business and Finance |
| LACATE | Lower Atmosphere Composition And Temperature Experiment | - | Business and Finance |
| LACTOZ | N/A | - | Business and Finance |
| LAGEOS | Laser Geodynamics Satellite | - | Business and Finance |
| LAGEOS-2 | Laser Geodynamics Satellite-2 | - | Business and Finance |
| LAI | Leaf Area Index | - | Business and Finance |
| LAM | Limited-area Model | - | Business and Finance |
| LAMBADA | Amazon Basin Experiment | - | Business and Finance |
| LAMMR | Large Antenna Multichannel Microwave Radiometer | - | Business and Finance |
| LAMMR | Large Antenna Multichannel Microwave Radiometer | - | Business and Finance |
| LAMP | Laboratoire Associe De Meteorologie Physique | - | Business and Finance |
| LAMPS | Limited-Area Mesoscale Prediction System | - | Business and Finance |
| LAMSS | Laser Air Motion Sensing System | - | Business and Finance |
| LAN | Local Area Network | - | Business and Finance |
| LANDSAT | Land Remote Sensing Satellite | - | Business and Finance |
| LANL | Los Alamos National Laboratory | - | Business and Finance |
| LANTEX | Lantau Experiment | - | Business and Finance |
| LAOL | Los Alamos Opacity Library | - | Business and Finance |
| LAPB | Local Analysis And Prediction Branch | - | Business and Finance |
| LAPS | Local Analysis And Prediction System | - | Business and Finance |
| LAPS | Local Area Prediction System | - | Business and Finance |
| LARC | Langley Research Center | - | Business and Finance |
| LARC | Limited Area Remote Collector | - | Business and Finance |
| LAS | Laboratory Of Atmospheric Science | - | Business and Finance |
| LAS | LAGEOS Apogee Stage | - | Business and Finance |
| LASA | Lidar Atmospheric Sounder And Altimeter | - | Business and Finance |
| LASERS | Learning About Science Easily And Readily | - | Business and Finance |
| LASP | Laboratory For Atmospheric And Space Physics | - | Business and Finance |
| LATAS | Laser True Airspeed System | - | Business and Finance |
| LAWS | Laser Atmospheric Wind Sounder | - | Business and Finance |
| LAWS | Low Altitude Wind Shear | - | Business and Finance |
| LBA/TRMM | Large Scale Biosphere-Atmosphere Experiment In Amazonia/Tropical Rainfall Measuring Mission | - | Business and Finance |
| LBJSC | Lydon B. Johnson Space Center | - | Business and Finance |
| LBJSC | Lydon B Johnson Space Center | - | Business and Finance |
| LBN | Lawrence Berkeley Laboratory | - | Business and Finance |
| LC | Inductance-capacitance | - | Business and Finance |
| LCC | Life Cycle Cost | - | Business and Finance |
| LCD | Liquid Crystal Display | - | Business and Finance |
| LCL | Lifting Consdensation Level | - | Business and Finance |
| LCM | Large Core Memory | - | Business and Finance |
| LDA | Local Data Acquisition | - | Business and Finance |
| LDAD | Local Data Acquisition And Dissemination | - | Business and Finance |
| LDAP | Lightweight Directory Access Protocol | - | Business and Finance |
| LDM | Local Data Manager | - | Business and Finance |
| LDN | Local Data Network | - | Business and Finance |
| LDR | LIDAR | - | Business and Finance |
| LDR | Linear Depolarization Ratio | - | Business and Finance |
| LDS | Lightning Detection System | - | Business and Finance |
| LDS | Linear Depolarization Ratio | - | Business and Finance |
| LDS | Loral Defense Systems | - | Business and Finance |
| LEADEX | Lead Experiment | - | Business and Finance |
| LEARN | Laboratory Experience In Atmospheric Research | - | Business and Finance |
| LEARN (PROJECT) | Laboratory Experience In Atmospheric Research | - | Business and Finance |
| LED | Light Emitting Diode | - | Business and Finance |
| LEDA | On-line Earthnet Data Access | - | Business and Finance |
| LERC | Lewis Research Center | - | Business and Finance |
| LES | Large-eddy Simulation | - | Business and Finance |
| LEST | Large Earth-Based Solar Telescope | - | Business and Finance |
| LEWEX | Labrador Extreme Waves Experiment | - | Business and Finance |
| LF | Low Frequency | - | Business and Finance |
| LFC | Large Format Camera | - | Business and Finance |
| LFM | Limited-area Fine Mesh | - | Business and Finance |
| LGSOWG | Landsat Ground Station Operators Working Group | - | Business and Finance |
| LHS | Left-hand Side | - | Business and Finance |
| LIDAR | Light Detection And Ranging Instrument | - | Business and Finance |
| LIE | Line Islands Experiment | - | Business and Finance |
| LIMS | Limb Infrared Monitor Of The Statosphere | - | Business and Finance |
| LINUX | N/A | - | Business and Finance |
| LIRIS | Loral IR Imaging System | - | Business and Finance |
| LIS | Library And Information Systems | - | Business and Finance |
| LIS | Lightning Imaging Sensor | - | Business and Finance |
| LISP | List Processing Language | - | Business and Finance |
| LITE | Lidar In Space Technology Experiment | - | Business and Finance |
| LL | Lincoln Laboratories | - | Business and Finance |
| LLC | Logical Link Control | - | Business and Finance |
| LLNL | Lawrence Livermore National Laboratory(ies) | - | Business and Finance |
| LLP | Lightning Location And Protection | - | Business and Finance |
| LLR | Lunar Laser Ranging | - | Business and Finance |
| LLWAS | Low-Level Wind Shear Alert System | - | Business and Finance |
| LM | Lumen | - | Business and Finance |
| LM | Large Model | - | Business and Finance |
| LME | Layer Management Entity | - | Business and Finance |
| LMER | Land Margin Ecosystems Research | - | Business and Finance |
| LMOS | Lake Michigan Ozone Study | - | Business and Finance |
| LNA | Low-noise Amplifier | - | Business and Finance |
| LNB | N/A | - | Business and Finance |
| LOC | Lines Of Code | - | Business and Finance |
| LOD2 | Lightweight Omega Digital Dropwindsonde | - | Business and Finance |
| LOE | Level Of Effort | - | Business and Finance |
| LOHSS | Local Hardware And Software Systems | - | Business and Finance |
| LOICZ | Land-Ocean Interactions In The Coastal Zone | - | Business and Finance |
| LORAN-C | Long Range (aid To) Navigation-C | - | Business and Finance |
| LOS | Loss Of Signal | - | Business and Finance |
| LOTREX | Working LORAN | - | Business and Finance |
| LOTUS | Lower Thermosphere And Upper Stratosphere | - | Business and Finance |
| LOWL | Low Degree Oscillations Experiment | - | Business and Finance |
