English abbreviations from clams to class
- CLAMS (Clear lane marking system (US))
- CLAN (Cute Little Awesome Newborn)
- CLAP (Carbohydrates, Lipid, Nucleic Acid, Protein)
- CLAPC/CLIPC (Contact lens associated/induced papillary conjunctivitis)
- CLAPS (Culture, Language, Arts, Programs, Services)
- CLAR (Communications Loading Analysis Report)
- CLARE (Contact lens associated red eye)
- CLAS (California Learning Assessment System)
- CLASP (Central Larkspur Area Specific Plan)
- CLASPI (Center for Law And Social Policy, Inc.)
- CLASS (Computerised Laser Sight System)