| Acronym | Meaning |
| LCPH | Localized Chemical Pseudopotential Hamiltonian |
| LCPLS | Logcontrast Partial Least Squares |
| LCR | Ligase Chain Reaction |
| LCR | Locus Control Region |
| LCRA | Linear Combination Of Rydberg Orbitals |
| LCRS | Leachate Collection And Removal System |
| LCS | Laboratory Control Samples |
| LCSPM-HO | Linear Combination Of Symmetry-adapted Products Of Morse Harmonic Oscillator (wave Functions) |
| LCST | Lower Critical Solution Temperature |
| LCTAO | Linear Combination Of Traveling Atomic Orbitals |
| LCTF | Liquid Crystal Tunable Filter |
| LCTV | Liquid Crystal Television |
| LCVD | Laser-induced Chemical Vapor Deposition |
| LCVO | Linear Combination Of Valence Orbitals |
| LCW | Liquid Core Waveguide |
| LD | Laser Desorption |
| LD | Laser Diode |
| LD | Lethal Dose |
| LD | Limits Of Detection |
| LD-KGC | Linz-Donawitz-Kawasaki Gas Control (steel Converter Furnaces) |
| LDA | Laser-Doppler Anemometer |
| LDA | Linear Diode Array |
| LDA | Linear Discriminant Analysis |
| LDA | Local-density Approximation |
| LDAR | Leak Detection And Repair |
| LDC | Less Developed Countries |
| LDC | Liq. Dynamic Compaction |
| LDD | Lightly Doped Drain |
| LDEF | Long Duration Exposure Facility (for Spacecraft Material Testing) |
| LDF | Laser Doppler Flowmetry |
| LDF | Local Density Functional |
| LDFT | Local Density-functional Theory |
| LDGUGA | Loop-driven Graphical Unitary-group Approach (in MC-SCF Calcns.) |
| LDH | Lactate Dehydrogenase |
| LDI | Laser Desorption Ionization |
| LDL | Low Density Lipoprotein |
| LDMOS | Laterally Diffused Metal Oxide Semiconductor |
| LDMS | Laser Desorption Mass Spectrometry |
| LDOS | Local Density Of States |
| LDPE | Low Density Polyethylene |
| LDPEX | Cross-linked |
| LDPO | Linearly Driven Parametric Oscillator (model In Energy Transfer Calcns. In Mol. Collisions) |
| LDQ | Linnett Double Quartet (equivalent To Nonpairing Spatial Orbital Theory) |
| LDR | Land Disposal Restriction(s) |
| LDR | Linear Dynamic Range |
| LDR | Low Dose Radiation |
| LDRP | Leak Detection And Repair Program |
| LDS | Leak Detection System |
| LDS | Linear Dichroism Spectrometry |
| LDT | Light Duty Truck |