MCLL
| Acronym | Definition |
|---|---|
| MCLL | Most Comfortable Listening Level (audiometry) |
| MCLL | Modern and Classical Languages and Literatures (academic department; various universities) |
| MCLL | Marine Corps Lessons Learned |
| MCLL | Missile Compartment Lower Level (compartment of a US Navy nuclear submarine) |
| MCLL | Meiklejohn Civil Liberties Library (Berkeley, CA) |