| Acronym | Meaning |
 | LRICBM | Limited Range ICBM |
 | LRIP | Low Rate Initial Production |
 | LRP | Logistics Release Point |
 | LRPE | Long-Range Planning Element |
 | LRS | Long Range Surveillance |
 | LRU | Line-Replaceable Unit |
 | LS | Landing Support -Lesotho (ISO 3166 Digram) - Liechtenstein (FIPS 10-4 Country Code) -locus Sigilli (Latin |
 | LSD | Landing Ship |
 | LSE | Least Squares Estimate/Error - London School Of Economics - London Stock Exchange |
 | LSI | Large-Scale Integration |
 | LSIF | Labour Sponsored Investment Fund |
 | LSL | Lesotho Loti (ISO 4217 Currency Code) |
 | LSND | Liquid Scintillator Neutrino Detector |
 | LSO | Lesotho (ISO 3166 Trigram) |
 | LSST | Large Synoptic Survey Telescope |
 | LST | Landing Ship |
 | LSVW | Light Support Vehicle |
 | LT | Lesotho (FIPS 10-4 Country Code) - Lithuania (ISO 3166 Digram) |
 | LT | Lieutenant |
 | LT | Lithuanian Language (ISO 639-1 Code) |
 | LTC | Long Term Costing |
 | LTC | Lieutenant-Colonel (U.S.) |
 | LTD | Limited |
 | LTDP | Long-Term Defence Plan |
 | LTG | Lieutenant General -Lightning (METAR Code) |
 | LTI | Linear Time-Invariant |
 | LTL | Lithuanian Litas (ISO 4217 Currency Code) |
 | LTP | Long-Term Potentiation |
 | LTU | Lithuania (ISO 3166 Trigram) |
 | LTZ | Luxembourgish Language (ISO 639-2 Code) |
 | LU | Lutetium |
 | LU | Tshiluba Language (ISO 639-1 Code) |
 | LU | Loonatics Unleashed |
 | LUB | Tshiluba Language (ISO 639-2 Code) |
 | LUCA | Last Universal Common Ancestor |
 | LUG | Linux User Group |
 | LUG | Luganda Language (ISO 639-2 Code) |
 | LULU | Locally Unwanted Land Use (urbanism) |
 | LUT | Limited User Test(ing) - Local User Terminal |
 | LUVW | Light Utility Vehicle |
 | LUX | Luxembourg (ISO 3166 Trigram) |
 | LV | Las Vegas -Latvia (ISO 3166 Digram) -Launch Vehicle - Leading Vehicle -Leave -Left Ventricle - Level Valve - Linking Verb |
 | LV | Latvian Language (ISO 639-1 Code) |
 | LVA | Latvia (ISO 3166 Trigram) |
 | LVEF | Left Ventricular Ejection Fraction |
 | LVL | Latvian Lats (ISO 4217 Currency Code) |
 | LW | Land Warrior - Low Water (nautical Charts) |
 | LW | Lawrencium (obsolete 1963) |
 | LWR | Laser Warning Receiver |
 | LWS | Land Warrior System |