ICL
- CAL Cargo Air Lines
- Clean (programming language)
- Climb phase
- Department of Chemistry, University of Oxford
- ICL Group Ltd.
- ICO (file format)
- Ice Lake (microprocessor)
- Icelandic Sign Language
- Idaho Conservation League
- Idiopathic CD4+ lymphocytopenia
- Image cash letter
- Imperial College London
- Implantable collamer lens
- Indian Confederation of Labour
- Indian Cricket League
- Inrush current limiter
- InterSwitch Trunk
- International Communist League (disambiguation)
- International Computers Limited
- International Confederation of Labor
- International Congress of Linguists
- International Consortium on Landslides
- International constitutional law
- International criminal law
- Isocitrate lyase