| Abbreviation | Definition |
|---|---|
| LSU | Lesbian and Student Union |
| LSU | Student Union |
| LTTE | Liberation Tigers of Tamil Ealam |
| LTU | Laurier Teachers Union |
| LTU | Lloyds Trade Union |
| LU | Liberal Union |
| LU | Local Union |
| LUCC | Libraries of Union County Consortium |
| LUMC | La Union Medical Center |
| LUMCC | Local Union Management Consultation Committee |
| LUMS | Labor Union Management System |
| LUMS | Lamoille Union Middle School |
| LUMUN | Lecturers Union of Memorial University of Newfoundland |
| LUMUN | Lecturers' Union of Memorial University of Newfoundland |
| LUSD | Lakeside Union School District |
| LUSD | Livingston Union School District |
| LUSD | Loomis Union School District |
| LUSU | Lakehead University Student Union |
| LUSU | Lancaster University Students' Union |
| LWU | Lithuanian Workers Union |