| label putar | Molekul atau kelompok yang mengandung elektron tidak berpasangan dan dapat dilampirkan ke molekul lain. |
| labil | |
| Labu dewar | |
| Ladenburg benzena | |
| laevorotatory.dll | |
| laevulose | |
| Lagrangian | |
| LAH | |
| Lahir, Max (1882–1970) | |
| lak | |
| lakmus | |
| laktam | |
| laktat | |
| laktim | |
| lakton | |
| laktosa | |
| lambda point | |
| lampu busur | |
| lampu hitam | |
| lampu neon | |
| langkah | |
| langkah penentu tarif | |
| lanolin | |
| lansfordite | |
| lanskap energi | |
| lantanida | |
| lantanoid | |
| lantanon | |
| lantanum | |
| lapis lazuli | |
| Lapisan appleton | |
| lapisan batas | |
| lapisan ganda lipid | |
| Lapisan Heaviside – Kennelly | |
| lapisan inversi | |
| lapisan ozon | |
| larutan | |
| larutan alkali | |
| larutan hipertonik | |
| larutan hipotonik | |
| larutan jenuh | |
| laser | |
| laser elektron bebas | |
| laser empat tingkat | |
| laser jenuh | |
| laser pewarna | |
| laser semikonduktor | |
| laser yang dapat disetel | |
| latar belakang kosmik neutrino | |
| Lavoisier, Antoine Laurent (1743–1794) | |
| lawrensi | |
| lazurite | |
| LCAO | |
| LCP | |
| L-dopa | |
| lechatelierite.dll | |
| ledakan | |
| ledakan sinar gamma | |
| LEED | |
| lektin | |
| Lemak Parafin | |
| lencana film | |
| lensa achromatic | |
| lensa anastigmatik | |
| lensa aplanatik | |
| lensa apokromatik | |
| lensa divergen | |
| lensa elektron | |
| Lensa fresnel | |
| lensa gravitasi | |
| lensa konvergen | |
| lensa lapangan | |
| lensa mata | |
| leusin | |
| Lewis, Gilbert Newton (1875–1946) | |
| Liebig, Justus von (1803–73) | |
| ligan | |
| ligase | |
| lignin | |
| liksiviasi | |
| lilin | |
| lilin internasional | |
| limonit | |
| lingkaran | |
| lingkaran besar | |
| lingkaran cahaya | |
| lipase | |
| lipid | |
| lipolisis | |
| lipoprotein | |
| liquidus | |
| lisin | |
| l-isomer | |
| l-isomer | |
| listrik | |
| listrik statis | |
| litarge | |
| liter | |
| lithia | |
| lithium aluminium hidrida | |
| lithium hidrida | |
| lithium hidroksida | |
| lithium karbonat | |
| lithium oksida | |
| lithium sulfat | |
| lithium tetrahydroaluminate (III) | |
| litium | |
| litium deuterida | |
| litium hidrogensarbonat | |
| LNG | |
| logam | |
| Logam babbit | |
| Logam kayu | |
| Logam monel | |
| logam mulia | |
| Logam Muntz | |
| logam nonferrous | |
| logam platinum | |
| Logam Rose | |
| logam senjata | |
| logam tipe A. | |
| logam tipe B. | |
| logaritma umum | |
| logika fuzzy | |
| logika gabungan emitor | |
| lokalisasi | |
| lompatan kuantum | |
| LSD | |
| lubang | |
| lubang balok | |
| lubang hitam | |
| lubang ozon | |
| luciferase | |
| luciferin | |
| luhur | |
| lulusan | |
| lumbung | |
| lumen | |
| luminescence | |
| LUMO | |
| lumut batu akik | |
| lutetium | |
| lux | |
| lyophilic | |
| lyophobic | |