ACL
- AC1 (disambiguation)
- ACI (disambiguation)
- ACL Cables
- ACL2
- ACLS (disambiguation)
- AFC Champions League Elite
- ATP citrate synthase
- Access-control list
- Acle railway station
- Administration for Community Living
- Afghanistan Champions League
- Agent Communications Language
- Aguaclara Airport
- Akar-Bale language
- Allegro Common Lisp
- American Classical League
- American Cornhole League
- Anterior cruciate ligament
- Anterior cruciate ligament injury
- Anti-cardiolipin antibodies
- Arctic Co-operatives Limited
- Arena Coventry Limited
- Arizona Complex League
- Association for Computational Linguistics
- Association of Costs Lawyers
- Asynchronous connection-oriented logical transport
- Ateliers et Chantiers de la Loire
- Atlantic City Line
- Atlantic Coast Line Railroad
- Atlantic Container Line
- Austin City Limits
- Austin City Limits Music Festival
- Australian Christian Lobby
- Australian Consumer Law
- Christian Liberal Alliance
- Domain-driven design
- Teilhol