| Acronym | Definition |
|---|
| ALCS | American League Championship Series (baseball) |
| ALCS | Airline Control System |
| ALCS | Authors' Licensing and Collecting Society (UK) |
| ALCS | Airborne Launch Control System |
| ALCS | Association for Low Countries Studies in Great Britain and Ireland (UK) |
| ALCS | Atonement Lutheran Church and School (Metairie, LA) |
| ALCS | Airlift Control Squadron |
| ALCS | Airfield Lighting Control and Monitoring System (also seen as ALCMS) |
| ALCS | Augmented Longitudinal Control System (NASA) |
| ALCS | Advance Liberty for Change Seminar (Centre for Civil Society; India) |
| ALCS | Analytical Laboratory Computer System |
| ALCS | Authors' Lending and Copyright Society (UK) |
| ALCS | Active Laser Countermeasure System |
| ALCS | Application Life Cycle Solution |
| ALCS | Automated Logistics Control System |
| ALCS | Acoustic Link Control Software |
| ALCS | Automated Laboratory Control System |